EVALUATION KIT AVAILABLE MAX8895V/MAX8895W/ MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration General Description The MAX8895_ USB-compliant linear battery chargers operate from either a USB port or dedicated charger with automatic detection of adapter type and USB enumeration capability. The MAX8895_ integrate the battery disconnect switch, current-sense circuit, MOSFET pass elements, and thermal regulation circuitry, and eliminate the external reverse-blocking Schottky diode to create the simplest and smallest stand-alone charging solutions. The MAX8895_ includes an automated detection of charge adapter type, making it possible to distinguish between USB 2.0 device, USB charger, and dedicated charger devices. Furthermore, the MAX8895_ include a USB enumeration function that automatically negotiates with a USB host, making it possible to achieve the highest current available from a USB 2.0 device or USB charger without processor intervention. The adapter type detection is compliant with USB 2.0 specification as well as USB charging Revision 1.1. The MAX8895_ controls the charging sequence for singlecell Li+ batteries from initial power-OK indication, through prequalification, fast-charge, top-off, and finally charge termination. Charging is controlled using constant current, constant voltage, and constant die-temperature (CCCVCTj) regulation for safe operation under all conditions. The maximum charging current is adaptively controlled by subtracting the system current from the input current limit, ensuring that the charging current is always maximized for any given operating condition. The MAX8895_ features optimized smart power control to make the best use of limited USB or adapter power. Battery charge current is set independently of the SYS_ input current limit. Power not used by the system charges the battery. Automatic input selection switches the system from battery to external power. This allows the application to operate without a battery, discharged battery, or dead battery. Other features include undervoltage lockout (UVLO), overvoltage protection (OVP), charge status flag, charge fault flag, power-OK monitor, battery thermistor monitor, charge timer, and a 3.3V output. The MAX8895_ operates from a +4.0V to +6.6V supply and include overvoltage protection up to +16V. The MAX8895_ is specified over the extended temperature range (-40NC to +85NC) and are available in a compact 2.36mm x 2.36mm, 25-bump WLP package (0.4mm pitch). Features S Enables Charging from a USB Port* S Automatic Detection of Adapter Type S Enumeration Capability Without Processor Intervention S USB Low-Speed Operation Without External Crystal (MAX8895V/MAX8895W/MAX8895X) S USB Full-Speed Operation Using an External Crystal (MAX8895Y) S Compliant with USB 2.0 Specification S Compliant with USB Charging Specification (Revision 1.1) S Adaptive Input Current Limit for Dedicated Charger S Input Overvoltage Protection to 16V S Automatic Current Sharing Between Battery Charging and System S Smart Power SelectorK Allows Operation with Discharged or No Battery S NTC Monitoring of Battery Temperature S No External MOSFETs Required S Thermal Regulation Prevents Overheating S 2A Shutdown Current S Tiny 2.36mm x 2.36mm, 25-Bump, 0.4mm Pitch WLP Package Applications Bluetooth(R) Headsets Charging Cradles Portable Devices Ordering Information and Typical Operating Circuit appear at end of data sheet. Bluetooth is a registered trademark of Bluetooth SIG. Smart Power Selector is a trademark of Maxim Integrated Products, Inc. *Protected by US Patent #6,507,172. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maximintegrated.com. 19-5205; Rev 4 9/12 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration ABSOLUTE MAXIMUM RATINGS BUS_ to AGND....................................................-0.3V to +16.0V XIN, XOUT, INT_3V3 to AGND..............................-0.3V to +4.0V ENU_EN, SUS_EN, RWU, D+, D-, PREQ, CHG, UOK, FLT, BAT_, SYS_, CEN, STDBY, DET_DONE, IBUS_DEF, CHG_TYPE to AGND......................-0.3V to +6.0V KB_TM, ISET, THM, IDN, CT to AGND.................................... -0.3V to (VINT_3V3 + 0.3V) DGND to AGND...................................................-0.3V to + 0.3V IBUS_, IBAT_, and ISYS_ Continuous Current............ 1800mARMS Continuous Power Dissipation (TA = +70NC) 25-Bump, 2.36mm x 2.36mm WLP (derate 19.34mW/NC above +70NC)...........................1560mW Operating Temperature....................................... -40NC to +85NC Junction Temperature......................................................+150NC Storage Temperature Range............................. -65NC to +150NC Soldering Temperature (reflow).......................................+260NC Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (THM = CEN = SUS_EN = AGND, VBAT_ = 4.2V, VBUS_, CT, PREQ, CHG, UOK, FLT, DET_DONE are unconnected, TA = -40NC to +85NC, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 6.6 V 14 V 500 650 ms USB-TO-SYS PREREGULATOR USB Operating Range Initial VBUS_ voltage before enabling charger USB Standoff Voltage VBAT_ = VSYS_ = 0V, IBUS_ < 650FA (max) BUS_OK Debounce Timer tUSB_DB USB Undervoltage Lockout Threshold USB Overvoltage Protection Threshold IDETECT USB Input Supply Current (Note 2) 4.0 Time from BUS_ within valid range until UOK logic-low UOK logic-low, VBUS_ rising, 100mV hysteresis Before initial detection of external device 3.85 4.0 4.15 UOK logic-low, VBUS_ falling USB 2.0 low-power device 3.75 3.9 4.05 UOK logic-low, VBUS_ falling USB 2.0 high-power device 3.95 4.1 4.25 UOK logic-low, VBUS_ falling Dedicated charger or USB charger UOK logic-low, VBUS_ rising, 100mV hysteresis MAX8895V/ Charge type detection, MAX8895W/ ISYS_ = IBAT_ = 0mA, MAX8895X VCEN = 0V MAX8895Y VSYS_ VSYS_ VSYS_ - 100mV + 50mV + 200mV 6.8 6.95 ISUSPEND IUSB_100mA USB 2.0 low-power device detected USB Input Current Limit 2 During suspend IENU V 2.5 100 MAX8895V/ MAX8895W/ MAX8895X 0.5 MAX8895Y 2.5 mA 100 TA = 0NC to +85NC 102.5 TA = -40NC to +85NC IUSB_500mA USB 2.0 high-power device detected ISUS 7.1 0.5 USB 2.0 enumeration in progress, IENUMERATE ISYS_ = IBAT_ = 0mA, VCEN = 0V Suspend mode, ISYS_ = IBAT_ = 0mA, VSTDBY = 3.3V V 500 0 During USB enumeration 40 45 55 IUSB_LP USB 2.0 low-power device detected 80 90 98 IUSB_HP USB 2.0 high-power device detected 460 475 490 mA Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration ELECTRICAL CHARACTERISTICS (continued) (THM = CEN = SUS_EN = AGND, VBAT_ = 4.2V, VBUS_, CT, PREQ, CHG, UOK, FLT, DET_DONE are unconnected, TA = -40NC to +85NC, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS VBUS_-to-VSYS_ OnResistance VBUS_ = VCEN = 5V, ISYS_ = 400mA VSYS_-to-VBAT_ Reverse Regulation When SYS is in regulation and charging stops, VSYS_ falling, 50mV hysteresis Input Limiter Soft-Start Time Input current ramp time Thermal-Limit Start Temperature MIN TYP MAX UNITS 200 320 mI VBAT_ VBAT_ VBAT_ - 80mV - 50mV - 20mV V 50 Fs TDIE_LIM Thermal-Limit Start Temperature Hysteresis 100 +110 NC 10 NC 5 %/NC Thermal-Limit Gain ISYS_ reduction/die temperature (above +110NC) VBUS_ Adaptive Current Regulation Threshold VBUS_ regulation threshold where input current limit is regulated for dedicated charger or USB charger VSYS_ + VSYS_ + 440mV 550mV V SYS_ Regulation Voltage VBAT_ > 3.45V, ISYS_ = 1mA to 1.6A, VBUS_ = VCEN = 5V VBAT_ + VBAT_ + 140mV 210mV V Minimum SYS Regulation Voltage VBUS_ = 6V, ISYS_ = 1mA to 1.6A, VCEN = 5V 3.3 3.4 3.55 V VBAT_UVLO_F VBAT_ falling 2.60 55 80 mI 2.85 3.1 VBAT_UVLO_R VBAT_ rising 2.75 3.00 3.25 CHARGER BAT_-to-SYS_ On-Resistance BAT_ Undervoltage Lockout ISYS_ = 200mA Charger Soft-Start Time BAT_ Leakage Current Charge-current ramp time 1 VBUS_ not connected 2 6 VBUS_ connected, VCEN = 5V 2 6 V ms FA PRECHARGE MODE BAT_ Precharge-Current Set Range BAT_ Prequalification Threshold IPCHG RISET = 30kI to 1.875kI, VBAT_ >1.4V (Note 3) IFCHG/10 A VBAT_PCHG_R VBAT_ rising 2.7 2.8 2.9 VBAT_PCHG_F VBAT_ falling 2.6 2.7 2.8 V FAST-CHARGE MODE BAT_ Charge-Current Set Range IFCHG VBUS_ = 5.5V (Note 3) 1.85 600 A mA RISET = 1.875kI 0000 1850 0000 RISET = 5kI 540 600 660 RISET = 30kI 90 100 110 VBAT_ rising threshold, where charging VBAT_FCHG_R current IFCHG is reduced to ITCHG 3.9 4.0 4.1 VBAT_ falling threshold, where charging current is increased to IFCHG 3.7 3.8 3.9 VBAT_FCHG_F Maxim Integrated 0.1 ISET = INT_3V3 (Note 3) BAT_ Charge-Current Accuracy, Charger Loop in Control BAT_ Fast-Charge Threshold RISET = 30kI to 1.875kI, VBAT_ >1.4V (Note 3) mA V 3 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration ELECTRICAL CHARACTERISTICS (continued) (THM = CEN = SUS_EN = AGND, VBAT_ = 4.2V, VBUS_, CT, PREQ, CHG, UOK, FLT, DET_DONE are unconnected, TA = -40NC to +85NC, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS TOP-OFF CHARGE MODE Top-Off Charge Current ITCHG BAT_ Charge Termination Current Range ICHG_DONE BAT_ Regulation Voltage VBAT_REG BAT_ Recharge Threshold VBAT_RECHG 0.6 x IFCHG RISET = 30kI to 1.875kI (Note 3) 10 RIDN = 240kI to 15kI IDN = INT_3V3 IBAT_ = 0mA A 160 80 TA = +25NC 4.179 4.200 4.221 TA = 0NC to +85NC 4.158 4.200 4.242 -100 -200 -300 Recharge threshold in relation to VBAT_ in DONE state going into top-off mode (Figure 20) mA V mV CHARGE TIMER Maximum Prequalification Time tPCHG Maximum Fast-Charge Time tFCHG Maintain-Charge Time From VCEN falling to end of prequalification charge mode, VBAT_ = 2.5V CT = 0.068FF 16 CT = AGND 20 From VCEN falling to VFLT falling CT = 0.068FF 100 CT = AGND 120 tMTCHG Timer Accuracy Min CT = 0.068FF 4 CT = AGND 5 Min Min CT = 0.068FF -30 +30 CT connected to AGND -30 +30 % Timer Extend Threshold Percentage of charge current below which timer clock operates at half speed 50 % Timer Suspend Threshold Percentage of charge current below which timer clock pauses 20 % ADAPTER TYPE DETECTION D- Current Sink IDM_SINK MAX8895V/MAX8895X/MAX8895Y 50 86 150 MAX8895W 64 86 102 FA D+ Source Voltage VDP_SRC 0.5 0.6 0.7 V D+ Detection Threshold VDAT_REF 0.25 0.32 0.40 V tDP_SRC_ON 100 ms D+ Source to High Current Time tDP_SRC_HC 40 ms D+ Source On-Time IDP_SRC = 0 to 200FA D- Pullup Resistor RDM_PU MAX8895V/MAX8895W/MAX8895X only, external series resistor = 33I D+ Pullup Resistor RDP_PU MAX8895Y only, external series resistor = 33I D+ Charger Detection Pullup Resistor RDP_CD_PU RDP_CD_PU connect to INT_3V3 D- Weak Current Sink IDM_CD_PD D- Logic-High Threshold 4 VDM_IH 1.425 1.500 1.575 kI 1.425 1.500 1.575 kI 200 330 600 kI 0.1 FA 2.0 V 0.8 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration ELECTRICAL CHARACTERISTICS (continued) (THM = CEN = SUS_EN = AGND, VBAT_ = 4.2V, VBUS_, CT, PREQ, CHG, UOK, FLT, DET_DONE are unconnected, TA = -40NC to +85NC, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Enumeration Time Limit tENUM Time from start of enumeration process until enumeration must be completed; if not completed, the MAX8895_ retries to enumerate Reconnect Timer tFAULT Time from failed enumeration to adapter type detection reenabled 3 s Time from enumeration fail at 500mA until Enumeration Fail to Reconnect enumeration is retried at 100mA or time from tENU_FAULT Timer enumeration fail at 100mA until reconnect timer is started 87 ms 100 ms Reenumeration Timer tRE_ENUM Time from when the MAX8895_ has entered suspend mode until it reenumerates, RWU = AGND Oscillator Frequency Accuracy MAX8895V/MAX8895X only (internal oscillator), TA = +25NC XIN Input Current MAX8895Y only, VXIN = VSTDBY = 3.3V XIN Logic-High Input Voltage MAX8895Y only XIN Logic-Low Input Voltage MAX8895Y only 5.91 10 s 6.00 2/3x VINT_3V3 6.09 MHz 10 FA VINT_3V3 V 0.4 V THM THM Cold Threshold TAMB_COLD When charging is suspended, rising threshold, 2% hysteresis 72 74 76 % of VINT_3V3 THM Hot Threshold TAMB_HOT When charging is suspended, falling threshold, 2% hysteresis 26 28 30 % of VINT_3V3 THM Threshold, Disabled When THM function is disabled, falling threshold, 2% hysteresis THM Input Leakage THM = AGND or INT_3V3 TA = +25NC TA = +85NC % of VINT_3V3 3 -0.1 0.001 +0.2 0.01 FA LOGIC I/O: CHG, FLT, UOK, CEN, PREQ, KB_TM, RWU, STDBY, SUS_EN, ENU_EN, DET_DONE, CHG_TYPE, IBUS_DEF High level 1.3 V Logic-Input Threshold Low level 0.4 Hysteresis Logic-Input Leakage Current VBUS_ = 0 to 5.5V Logic-Low Output Voltage (CHG, FLT, UOK, PREQ, DET_DONE, CHG_TYPE Only) Sinking 10mA Logic-High Output-Leakage Current (CHG, FLT, UOK, PREQ, DET_DONE, CHG_ TYPE Only) VSYS_ = 5.5V Maxim Integrated 50 TA = +25NC 0.001 TA = +85NC 0.01 mV 1 35 100 TA = +25NC 0.001 1 TA = +85NC 0.01 FA mV FA 5 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration ELECTRICAL CHARACTERISTICS (continued) (THM = CEN = SUS_EN = AGND, VBAT_ = 4.2V, VBUS_, CT, PREQ, CHG, UOK, FLT, DET_DONE are unconnected, TA = -40NC to +85NC, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS USB DATA INTERFACE Differential-Receiver Input Sensitivity |VD+ - VD-| Differential-Receiver Common-Mode Voltage 0.2 V 0.8 D+, D- Input Impedance 2.5 300 D+, D- Output Low Voltage VOL RLOAD = 1.5kI from VD- to 3.6V D+, D- Output High Voltage VOH RLOAD = 15kI from D+ and D- to AGND kI 2.8 V 3.6 V 11 I Excludes external resistor BUS_ Idle Time tIDLE Only valid when an adapter type is detected as a USB 2.0 device; time BUS_ is inactive until charging current is reduced to ISUSPEND 3 ms USB Host Remote Wake-Up Timer tRWU Time delay from when the MAX8895_ is put into suspend mode until they request the host for a remote wake-up 100 ms D+, D- Rise Time (Note 5) tRISE tFALL Rise-/Fall-Time Matching (Note 5) Output-Signal Crossover Voltage (Note 5) 7 0.3 Driver Output Impedance D+, D- Fall Time (Note 5) 2 V MAX8895V/MAX8895W/MAX8895X only, CL = 50pF to 600pF, (Figures 5 and 6) 75 250 MAX8895Y only, CL = 50pF (Figures 5 and 6) 4 20 MAX8895V/MAX8895W/MAX8895X only, CL = 50pF to 600pF (Figures 5 and 6) 75 250 MAX8895Y only, CL = 50pF (Figures 5 and 6) 4 20 MAX8895V/MAX8895W/MAX8895X only, CL = 50pF to 600pF (Figures 5 and 6) 80 120 MAX8895Y only, CL = 50pF (Figures 5 and 6) 90 110 MAX8895V/MAX8895W/MAX8895X only, CL = 50pF to 600pF (Figures 5 and 6) 1.3 2.0 MAX8895Y only, CL = 50pF (Figures 5 and 6) 1.3 2.0 VBUS_= 5V, IINT_3V3 = 0 to 10mA 3.0 ns ns % V INT_3V3 REGULATOR INT_3V3 Voltage 3.3 3.6 V ESD PROTECTION (D+, D-, VBUS_) Human Body Model VBUS_ bypassed with 1FF to AGND Q8 kV Note 1: Specifications are 100% production tested at TA = +25NC. Limits over the operating temperature range are guaranteed by design and characterization. Note 2: Sum of input current limit and current used for INT_3V3. Note 3: Maximum charging current is adaptively regulated to IIN_LIM - ISYS_ with a maximum value of ICHG. Note 4: All devices are 100% production tested at TA = +25NC. Limits over the operating temperature range are guaranteed by design. Note 5: Guaranteed by design, not production tested. 6 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Typical Operating Characteristics (VBAT_ = 4.2V, VBUS_ = 5V, ISET = IDN = CT = SUS_EN = INT_3V3, STDBY = ENU_EN = RWU = CEN = KB_TM = AGND, circuits of Figures 4 and 5 (MAX8895V/MAX8895X and MAX8895Y, respectively), TA = +25NC, unless otherwise noted.) 200 150 100 SUS_EN = ENU_EN = CEN = AGND STDBY = INT_3V3 50 0 2 4 6 8 10 12 14 0.5 16 VBAT_ = 4.2V CEN = INT_3V3 SUS_EN = ENU_EN = AGND 2.0 1.5 1.0 0.5 0 0 2 4 6 8 10 12 14 0 16 2 4 6 8 10 12 14 16 VBUS_ (V) MAX8895Y VBUS_ INPUT SUPPLY CURRENT vs. VBUS_ (SUSPEND MODE) MAX8895Y VBUS_ INPUT SUPPLY CURRENT vs. VBUS_ (CHARGER ENABLED) MAX8895Y VBUS_ INPUT SUPPLY CURRENT vs. VBUS_ (CHARGER DISABLED) 350 300 250 200 150 100 BATTERY UNCONNECTED CEN = AGND 4.5 50 4.0 3.5 3.0 2.5 2.0 1.5 1.0 4.5 0 2 4 6 8 10 12 14 16 3.0 2.5 2.0 1.5 1.0 0 0 2 4 6 8 10 12 14 16 0 2 4 6 8 10 12 14 16 VBUS_ (V) VBUS_ (V) BATTERY LEAKAGE CURRENT vs. BATTERY VOLTAGE BATTERY LEAKAGE CURRENT vs. TEMPERATURE CHARGE CURRENT vs. BATTERY VOLTAGE (DEDICATED CHARTER) 1.8 1.6 1.4 1.2 1.0 0.8 0.6 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.4 BUS_ UNCONNECTED CEN = AGND 0.2 0 3.0 3.5 4.0 VBATT (V) Maxim Integrated ENU_EN = SUS_EN = AGND, RISET = 5kI 600 500 400 300 200 100 0.2 0 0 4.5 700 CHARGE CURRENT (mA) MAX8895W/X/Y toc07 2.0 MAX8895W/X/Y toc09 VBUS_ (V) LEAKAGE CURRENT (A) 0 3.5 0.5 0.5 0 VBAT_ = 4.2V CEN = INT_3V3 4.0 INPUT SUPPLY CURRENT (mA) 400 5.0 INPUT SUPPLY CURRENT (mA) MAX8895W/X/Y toc04 CEN = STDBY = AGND 450 MAX8895W/X/Y toc06 VBUS_ (V) MAX8895W/X/Y toc05 VBUS_ (V) 500 INPUT SUPPLY CURRENT (A) 1.0 0 0 LEAKAGE CURRENT (A) 1.5 2.5 INPUT SUPPLY CURRENT (mA) 250 2.0 MAX8895W/X/Y toc02 300 BATT UNCONNECTED SUS_EN = ENU_EN = CEN = AGND MAX8895W/X/Y toc08 INPUT SUPPLY CURRENT (A) 350 2.5 INPUT SUPPLY CURRENT (mA) MAX8895W/X/Y toc01 400 MAX8895V/W/X VBUS_ INPUT SUPPLY CURRENT vs. VBUS_ (CHARGER DISABLED) MAX8895V/W/X VBUS_ INPUT SUPPLY CURRENT vs. VBUS_ (CHARGER ENABLED) MAX8895W/X/Y toc03 MAX8895V/W/X VBUS_ INPUT SUPPLY CURRENT vs. VBUS_ (SUSPEND MODE) -40 -15 10 35 TEMPERATURE (NC) 60 85 2.0 2.5 3.0 3.5 4.0 4.5 BATTERY VOLTAGE (V) 7 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Typical Operating Characteristics (continued) (VBAT_ = 4.2V, VBUS_ = 5V, ISET = IDN = CT = SUS_EN = INT_3V3, STDBY = ENU_EN = RWU = CEN = KB_TM = AGND, circuits of Figures 4 and 5 (MAX8895V/MAX8895X and MAX8895Y, respectively), TA = +25NC, unless otherwise noted.) 50 40 30 20 400 300 200 4.0 4.5 2.5 BATTERY VOLTAGE (V) 4.205 4.200 4.195 4.190 SYS_ OUTPUT VOLTAGE (V) 4.210 4.185 4.180 10 35 3.0 60 4.400 4.375 4.350 4.325 4.300 4.275 4.250 4.225 4.200 4.175 4.150 4.125 4.100 4.075 3.5 4.0 MAX8895W/X/Y toc12 -40 4.5 BUS_ UNCONNECTED DROPOUT MEASURED WHEN SYS_ DECREASES BY 10% 100 80 60 40 6 4.5 7 ISYS_ = 0A 4.0 3.5 3.0 ISYS_ = 100mA 2.5 2.0 1.5 1.0 0.5 VBUS_ = 5V 0 8 2.0 VBAT_ = 4.2V 4.30 VSYS_ SUPPLEMENTED BY VBUS_ 4.20 4.10 SYSTEM LOAD SWITCH IN DROPOUT 4.00 3.80 4.40 2000 4.0 4.5 VBAT_ = 4.2V, NOKIA AC-10U 4.35 4.30 VSYS_ SUPPLEMENTED BY VBUS_ 4.25 4.20 4.15 4.10 4.05 4.00 SYSTEM LOAD SWITCH IN DROPOUT 3.95 1500 3.5 SYS_ OUTPUT VOLTAGE vs. LOAD CURRENT (DEDICATED CHARGER) 0 1000 3.0 SYS_ OUTPUT VOLTAGE vs. LOAD CURRENT (HIGH-POWER USB MODE) 3.90 ISYS_ (mA) 2.5 VBATT (V) 20 500 85 60 VBUS_ (V) 4.40 SYS_ OUTPUT VOLTAGE (V) MAX8895W/X/Y toc16 140 5 35 5.0 VBAT_ = 4.2V 4 10 SYS_ OUTPUT VOLTAGE vs. BATTERY VOLTAGE ISYS_ = 20mA 3 85 SYS_ DROPOUT VOLTAGE vs. LOAD CURRENT 0 -15 TEMPERATURE (C) ISYS_ = 0mA TEMPERATURE (C) 120 603 SYS_ OUTPUT VOLTAGE vs. VBUS_ MAX8895W/X/Y toc13 BATTERY REGULATION VOLTAGE (V) 4.215 -15 604 BATTERY VOLTAGE (V) BATTERY REGULATION VOLTAGE vs. AMBIENT TEMPERATURE -40 605 600 2.0 SYS_ OUTPUT VOLTAGE (V) 3.5 SYS_ OUTPUT VOLTAGE (V) 3.0 MAX8895W/X/Y toc14 2.5 606 601 ENU_EN = SUS_EN = AGND 0 2.0 607 602 ENU_EN = INT_3V3, SUS_EN = AGND 0 SYS_ DROPOUT VOLTAGE (mV) 608 100 10 8 609 MAX8895W/X/Y toc15 60 500 610 MAX8895W/X/Y toc18 70 CHARGER IN DROPOUT MAX8895W/X/Y toc17 CHARGE CURRENT (mA) 80 600 CHARGE CURRENT (DEDICATED CHARGER) vs. AMBIENT TEMPERATURE CHARGE CURRENT (mA) 90 CHARGE CURRENT (mA) MAX8895W/X/Y toc10 100 MAX8895W/X/Y toc11 CHARGE CURRENT vs. BATTERY VOLTAGE (HIGH-POWER USB) CHARGE CURRENT vs. BATTERY VOLTAGE (LOW-POWER USB) 3.90 0 500 1000 ISYS_ (mA) 1500 2000 0 500 1000 1500 2000 ISYS_ (mA) Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Typical Operating Characteristics (continued) (VBAT_ = 4.2V, VBUS_ = 5V, ISET = IDN = CT = SUS_EN = INT_3V3, STDBY = ENU_EN = RWU = CEN = KB_TM = AGND, circuits of Figures 4 and 5 (MAX8895V/MAX8895X and MAX8895Y, respectively), TA = +25NC, unless otherwise noted.) 50mA CHARGE CURRENT 3.20 900 4.20 VBAT_ 4.10 VBATT (V) VINT_3V3 (V) 100mA CHARGE CURRENT 1000 3.15 800 700 4.00 600 3.90 3.80 3.10 3.70 3.05 VBAT_ = 4V 4.0 5.0 6.0 7.0 200 100 0 3.50 8.0 0 25 50 75 100 125 150 175 200 225 250 275 300 TIME (min) CHARGE PROFILE (USB 2.0 CHARGER) 4.10 400 VBAT_ 350 300 MOTOROLA BC60 860mAh CCT = 0.2F RISET = 3.74kI RIDN = 243kI 3.80 3.70 250 200 150 3.60 3.50 100 IBAT_ 3.40 50 3.30 0 3.6 3.1 2.6 2.1 1.6 1.1 0.6 0.1 0 0 25 50 75 100 125 150 175 200 225 250 275 300 TIME (min) 1.0 2.0 3.0 4.0 5.0 TIME (x 10-7) (s) 6.0 DEDICATED CHARGER CONNECT MAX8895Y EYE DIAGRAM MAX8895W/X/Y toc23 MAX8895W/X/Y toc24 4.0 3.5 D+, D- SIGNALS (V) MAX8895W/X/Y toc22 450 D+, D- SIGNALS (V) 4.20 MAX8895W/X/Y toc21 500 IBATT (mA) VBATT (V) MAX8895V/W/X EYE DIAGRAM 4.30 3.90 300 IBAT_ VBUS_ (V) 4.00 400 3.60 3.00 3.0 500 MOTOROLA BC60 860mAh CCT = 0.2F RISET = 1.87kI RIDN = 243kI IBATT (mA) 3.30 3.25 4.30 MAX8895W/X/Y toc19 3.35 MAX8895W/X/Y toc20 CHARGE PROFILE (NOKIA AC-10 CHARGER) INT_3V3 VOLTAGE vs. BUS_ VOLTAGE 3.0 2.5 5V/div VBUS 0V 5V/div VSYS 0V 2.0 1.5 5V/div 1.0 0.5 VD+ 0 -0.5 0 Maxim Integrated 0V 5V/div 0V VD- 1.0 2.0 3.0 4.0 5.0 6.0 TIME (x 10-8) (s) 7.0 8.0 200ms/div 9 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Typical Operating Characteristics (continued) (VBAT_ = 4.2V, VBUS_ = 5V, ISET = IDN = CT = SUS_EN = INT_3V3, STDBY = ENU_EN = RWU = CEN = KB_TM = AGND, circuits of Figures 4 and 5 (MAX8895V/MAX8895X and MAX8895Y, respectively), TA = +25NC, unless otherwise noted.) MAX8895V/W/X HIGH-POWER 2.0 DEDICATED CHARGER DISCONNECT MAX8895W/X/Y toc25 VBUS_ MAX8895W/X/Y toc26 5V/div 0V 5V/div VINT_3V3 5V/div VBUS 0V 0V 500mA/div IBUS VSYS_ 5V/div VD+ VBAT_ 0V 5V/div 0V VD- RSYS_ = 100I 0A 5V/div 0V 5V/div 0V 200ms/div 400ms/div MAX8895Y USB HIGH-POWER 2.0 CONNECT MAX8895V/W/X USB HIGH-POWER 2.0 DISCONNECT MAX8895W/X/Y toc27 VBUS MAX8895W/X/Y toc28 5V/div VBUS_ 0V IBUS_ 5V/div 0V 100mA/div 500mA/div 0A IBUS VD+ 5V/div 0V VD- 5V/div 0V 0mA 2V/div VD+ 0V 400ms/div 0V 20ms/div MAX8895Y USB HIGH-POWER 2.0 DISCONNECT MAX8895V/W/X USB AUTOSUSPEND MAX8895W/X/Y toc30 MAX8895W/X/Y toc29 VBUS_ 2V/div 5V/div 0V 200mA/div IBUS_ VD+ VD- 0V 2V/div 0V 0mA VD+ 2V/div VFLT 1V/div 0V 0V RSYS_ = 100I 2ms/div 10 2V/div IBUS_ 200mA/div 0V VD- 2V/div RSYS_ = 100I VD- 0mA 1ms/div Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Typical Operating Characteristics (continued) (VBAT_ = 4.2V, VBUS_ = 5V, ISET = IDN = CT = SUS_EN = INT_3V3, STDBY = ENU_EN = RWU = CEN = KB_TM = AGND, circuits of Figures 4 and 5 (MAX8895V/MAX8895X and MAX8895Y, respectively), TA = +25NC, unless otherwise noted.) MAX8895Y USB AUTOSUSPEND MAX8895V/W/X USB RESUME MAX8895W/X/Y toc31 VD+ MAX8895W/X/Y toc32 VD+ 2V/div VD- 0V 0V 2V/div 2V/div VD- 0V VFLT 0V VFLT 1V/div 1V/div IBUS_ 0V IBUS_ 2V/div 0V 200mA/div 200mA/div 0mA 0mA 1ms/div 1s/div MAX8895Y USB RESUME PREQUALIFICATION TIMEOUT vs. CT CAPACITANCE MAX8895W/X/Y toc33 VD+ VD- 0V 2V/div VFLT 0V 2V/div 0V PREQUALIFICATION TIMEOUT (s) 2V/div IBUS_ 200mA/div MAX8895W/X/Y toc34 1600 1400 1200 1000 800 600 400 200 0mA 0 0 1s/div 20,000 40,000 60,000 80,000 100,000 CCT (pF) FAST-CHARGE TIMEOUT vs. CT CAPACITANCE MAX8895W/X/Y toc35 10,000 FAST-CHARGE TIMEOUT (s) 9,000 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0 0 20,000 40,000 60,000 80,000 100,000 CCT (pF) Maxim Integrated 11 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Pin Configurations TOP VIEW (BUMP SIDE DOWN) MAX8895W 1 2 3 4 5 A ISET STDBY BAT_A SYS_A BUS_A B IDN CHG_ TYPE BAT_B SYS_B BUS_B C ENU_EN DET_DONE UOK KB_TM AGND D SUS_EN IBUS_DEF CEN FLT D+ E CT THM INT_3V3 DGND D- + WLP TOP VIEW (BUMP SIDE DOWN) 1 TOP VIEW (BUMP SIDE DOWN) MAX8895V MAX8895X 2 3 4 5 1 2 3 4 5 + + A ISET STDBY BAT_A SYS_A BUS_A A ISET STDBY BAT_A SYS_A BUS_A B IDN CHG BAT_B SYS_B BUS_B B IDN CHG BAT_B SYS_B BUS_B C ENU_EN PREQ UOK KB_TM AGND C XIN PREQ UOK KB_TM AGND D SUS_EN RWU CEN FLT D+ D XOUT RWU CEN FLT D+ E CT THM INT_3V3 DGND D- E CT THM INT_3V3 DGND D- WLP 12 MAX8895Y WLP Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Pin Description PIN A1 MAX8895W ISET NAME MAX8895V/ MAX8895X ISET MAX8895Y ISET Maximum Fast-Charge Current Selection. Connect a resistor from ISET to AGND to set the fast-charge current from 0.1A to 1.85A. IFCHG = 3000/RISET If ISET is connected to INT_3V3 the default IFCHG is set as maximum charge current. ISET can also be used to monitor the actual current charging the battery. See the Monitoring Charge Current section for details. Standby Mode Enable. Connect STDBY to AGND to enter automatic detect mode. In automatic detect mode, the MAX8895V/MAX8895W/MAX8895X determine when to enter suspend mode depending on the status of the SUS_EN logic input. When using the MAX8895Y, the IC always starts in automatic suspend mode. Connect STDBY to INT_3V3 or drive logic-high to force the MAX8895_ into suspend mode regardless of external conditions. A2 STDBY STDBY STDBY A3 BAT_A BAT_A BAT_A B3 BAT_B BAT_B BAT_B A4 SYS_A SYS_A SYS_A B4 SYS_B SYS_B SYS_B A5 BUS_A BUS_A BUS_A B5 BUS_B BUS_B BUS_B B1 IDN Maxim Integrated IDN FUNCTION IDN Li+ Battery Connection (VBAT_). Connect a single-cell Li+ battery from VBAT_ to DGND. The battery charges from VSYS_ when a valid source is present at VBUS_. VBAT_ powers VSYS_ when VBUS_ power is not present, or when the VSYS_ load exceeds the input current limit. Bypass VBAT_ to DGND with a 10FF X5R or X7R ceramic capacitor. Both BAT_A and BAT_B must be connected together externally. System Supply Output (VSYS_). VSYS_ is connected to VBAT_ through an internal 55mI system load switch when VBUS_ is invalid, or when the VSYS_ load is greater than the input current limit. When a valid voltage is present at VBUS_, VSYS_ is limited to 4.35V when using the MAX8895V/MAX8895X/ MAX8895Y, and 4.53V when using the MAX8895W. When the system load current (ISYS_) exceeds the VBUS_ current limit VBAT_ also powers VSYS_ to maintain the load current. Bypass VSYS_ to DGND with a 10FF X5R or X7R ceramic capacitor. Both SYS_A and SYS_B must be connected together externally. USB Power Input (VBUS_). During initial connection of an external device, the MAX8895_ identifies the type of connection established and set the input current limit accordingly. Bypass VBUS_ to DGND with a 10FF X5R or X7R ceramic capacitor. Both BUS_A and BUS_B must be connected together externally. Charge Termination Current Threshold. Connect a resistor from IDN to AGND to set the termination current threshold from 10mA to 160mA. ITERM = 2400/RIDN If IDN is connected to INT_3V3, the termination current is set to the default ICHG_DONE threshold. 13 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Pin Description (continued) PIN MAX8895W NAME MAX8895V/ MAX8895X MAX8895Y FUNCTION -- CHG CHG Active-Low, Charging Indicator. CHG is an open-drain output that is pulled low when the battery is in prequalification mode, fast-charge mode, or top-off states. Otherwise, CHG is high impedance. CHG_TYPE -- -- CHG_TYPE is used to indicate capacity of input current. IF CHG_TYPE is high, the input current can be greater than or equal to 500mA. If CHG_TYPE is low, the input current is 100mA from the USB 2.0 host. -- -- XIN Crystal Oscillator Input. Connect XIN to one side of a parallel resonant 12MHz 0.25% crystal and a capacitor to AGND. XIN can also be driven by an external clock referenced to INT_3V3. -- Automatic Enumeration Enable. Connect ENU_EN to AGND to allow the MAX8895V/MAX8895X to automatically perform enumeration. Connect to INT_3V3 or drive logic-high to force the input current limit to 100mA without performing an adapter type detection. B2 -- ENU_EN C1 ENU_EN -- -- Automatic Enumeration Enable. Connect ENU_EN to AGND to allow the MAX8895W to automatically perform enumeration. By connecting ENU_EN to INT_3V3 or drive logic-high, disables automatic enumeration and sets the input current limit to level determined by the IBUS_DEF if a USB 2.0 device is detected. -- PREQ PREQ Active-Low, Prequalification Charging Output. PREQ is an open-drain output that is pulled low when the charger enters the prequalification state. DET_DONE -- -- Active-Low Adapter-Type Detection Done Output. DET_DONE is an opendrain output that is pulled low when adapter detection is completed. DET_ DONE is high impedance in suspend mode. C3 UOK UOK UOK Active-Low, VBUS_ Power-OK Output. UOK is an open-drain output that is pulled low when a valid input is detected at VBUS_. C4 KB_TM KB_TM KB_TM Keyboard Test Mode. In normal operation, connect KB_TM to AGND. This input is only used during USB certification. C5 AGND AGND AGND Analog Ground. Both AGND and DGND should be connected together at the negative terminal of the battery. -- -- XOUT Crystal Oscillator Output. Connect XOUT to one side of a parallel resonant 12MHz Q0.25% crystal and a capacitor to AGND. Leave XOUT unconnected if XIN is driven by an external clock. C2 D1 SUS_EN SUS_EN -- Automatic Suspend Mode Detection Enable. Connect SUS_EN to AGND to disable the automatic suspend mode detection. Connect SUS_EN to INT_3V3 or drive logic-high to enable the automatic detection of suspend mode. -- RWU RWU Remote Wake-up. Connect RWU to AGND or logic-low for remote wakeups whenever the device is put into suspend mode and the supervisor determines that more current is needed. D2 IBUS_DEF 14 -- -- Sets USB Input Current if Adapter is Detected as a USB 2.0 Device and ENU_EN is Logic-High. If IBUS_DEF is connected high, the input current limit is set to 500mA. If IBUS_DEF is connected low or to ground, the input current limit is set to 100mA. Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Pin Description (continued) PIN D3 MAX8895W CEN NAME MAX8895V/ MAX8895X CEN MAX8895Y FUNCTION CEN Charger Enable Input. Connect CEN to AGND to enable battery charging when a valid source is connected at VBUS_. Connect CEN to INT_3V3 or drive logic-high to disable battery charging. In this condition the USB state machine is still active, and VSYS_ is powered from VBUS_ under normal conditions and supplemented from VBAT_ if sufficient current is not available from VBUS_ input. D4 FLT FLT FLT Active-Low Fault Output. FLT is an open-drain output that is pulled low when the battery charger timer expires before prequalification or fast-charge completes. FLT is also pulled low during adapter type detection or if USB enumeration fails. D5 D+ D+ D+ USB D+ signal. Connect D+ to a USB "B" connector through a 33I series resistor. The 1.5kI D+ pullup resistor is internal to the device (for MAX8895Y only). CT Timer Set Capacitor. Connect a capacitor from CT to AGND to set the fault timers for prequalification and fast-charge. tPREQUAL = 16min x (CCT/0.068FF) tFCHG = 100min x (CCT/0.068FF) tMTCHG = 4min x (CCT/0.068FF) If CT is connected directly to AGND, the default timers are used. E1 CT CT Thermistor Input. Connect a negative temperature coefficient (NTC) thermistor that has good thermal contact with the battery from THM to AGND. Connect a resistor equal to the thermistor at TA = +25NC resistance from THM to INT_3V3. Charging is suspended when the thermistor is outside the hot and cold limits. Connect THM to AGND to disable the thermistor temperature sensor. E2 THM THM THM E3 INT_3V3 INT_3V3 INT_3V3 E4 DGND DGND DGND Digital Ground. Both AGND and DGND should be connected together at the negative terminal of the battery. E5 D- D- D- USB D- Signal. Connect D- to a USB "B" connector through a 33I series resistor. The 1.5kI D- pullup resistor is internal to the device (for MAX8895V/ MAX8895W/MAX8895X only). Maxim Integrated LDO Output. INT_3V3 is the output of an LDO that powers the internal circuitry. INT_3V3 is powered from the VBUS_ input. Connect a 0.1FF capacitor from INT_3V3 to AGND. 15 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration VBUS_ OUT OF RANGE VBUS_ VALID BUS_A BUS_B USB POWER MANAGEMENT UOK SET INPUT CURRENT LIMIT ILIM ISYS_ SET INPUT CURRENT LIMIT SYS_A SYS_B TO SYSTEM LOAD Li+ BATTERY CHARGER AND SYS LOAD SWITCH ISET ILIMISYS ICHG IC THERMAL REGULATION ICHG_MAX ILIM CHARGER CURRENT VOLTAGE CONTROL RISET BAT_A BAT_B BAT+ USB ADAPTER TYPE DETECTION AND ENUMERATION BAT- VBUS RD+ D+ RDD- RT THERMISTOR MONITOR D+ MAX8895V MAX8895X D- THM NTC RTB INT_3V3 GND 3.3V FOR INTERNAL USB TRANSCEIVER CINT_3V3 SUPPORT REMOTE WAKE-UP FORCE REMOTE WAKE-UP AUTOMATED SUSPEND ENABLED AUTOMATED SUSPEND DISABLED AUTOMATIC ENUMERATION DISABLED AUTOMATIC ENUMERATION ENABLED KEYBOARD TEST MODE ENABLED KEYBOARD TEST MODE DISABLED FORCED STANDBY MODE AUTOMATIC STANDBY MODE RWU SUS_EN CHARGE TERMINATION AND MONITOR USB INTERFACE LOGIC ENU_EN CHG CHARGING TERMINATED CHARGING IN PROGRESS PREQ PRECHARGING TERMINATED PRECHARGING IN PROGRESS IDN RIDN KB_TM FLT CT STDBY CHARGE TIMER POR CCT CEN INT_3V3 DGND NO FAULT FAULT CHARGER DISABLED CHARGER ENABLED AGND Figure 1. MAX8895V/MAX8895X Block Diagram 16 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration VBUS_ OUT OF RANGE VBUS_ VALID BUS_A BUS_B USB POWER MANAGEMENT UOK INPUT CURRENT LIMIT ILIM ISYS_ SET INPUT CURRENT LIMIT SYS_A SYS_B TO SYSTEM LOAD Li+ BATTERY CHARGER AND SYS LOAD SWITCH ISET ILIMISYS ICHG IC THERMAL REGULATION ICHG_MAX ILIM CHARGER CURRENT VOLTAGE CONTROL RISET BAT_A BAT_B BAT+ USB ADAPTER TYPE DETECTION AND ENUMERATION BAT- VBUS RD+ D+ RDD- RT THERMISTOR MONITOR D+ THM MAX8895Y D- NTC RTB INT_3V3 GND 3.3V FOR INTERNAL USB TRANSCEIVER CINT_3V3 SUPPORT REMOTE WAKE-UP FORCE REMOTE WAKE-UP KEYBOARD TEST MODE ENABLED KEYBOARD TEST MODE DISABLED FORCED STANDBY MODE AUTOMATIC STANDBY MODE RWU USB INTERFACE LOGIC CHARGE TERMINATION AND MONITOR KB_TM STDBY CHG CHARGING TERMINATED CHARGING IN PROGRESS PREQ PRECHARGING TERMINATED PRECHARGING IN PROGRESS IDN RIDN POR FLT CT CHARGE TIMER INT_3V3 NO FAULT FAULT CCT XIN CEN OSCILLATOR XOUT DGND CHARGER DISABLED CHARGER ENABLED AGND Figure 2. Differential Input Configuration Maxim Integrated 17 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration VBUS_ OUT OF RANGE VBUS_ VALID BUS_A BUS_B USB POWER MANAGEMENT UOK INPUT CURRENT LIMIT ILIM ISYS_ SET INPUT CURRENT LIMIT SYS_A SYS_B Li+ BATTERY CHARGER AND SYS LOAD SWITCH ISET ILIMISYS IC THERMAL REGULATION ILIM USB ADAPTER TYPE DETECTION AND ENUMERATION VBUS D+ D- ICHG ICHG_MAX CHARGER CURRENT VOLTAGE CONTROL RISET BAT_A BAT_B BAT+ BAT- MAX8895W THERMISTOR MONITOR D+ THM NTC RTHM DINT_3V3 GND 3.3V FOR USB TRANSCEIVER CINT_3V3 AUTOMATIC SUSPEND ENABLED AUTOMATIC SUSPEND DISABLED SUS_EN AUTOMATIC SUSPEND ENABLED AUTOMATIC SUSPEND DISABLED ENU_EN KEYBOARD TEST MODE ENABLED KEYBOARD TEST MODE DISABLED KB_TM FORCED STANDBY MODE AUTOMATIC STANDBY MODE STDBY ADAPTER DETECTION IN PROGRESS ADAPTER DETECTION COMPLETE DET_DONE R500mA INPUT CURRENT LIMIT 100mA MAX. INPUT CURRENT LIMIT CHG_TYPE INPUT CURRENT LIMIT SET TO 500mA INPUT CURRENT LIMIT SET TO 100mA TO SYSTEM LOAD CHARGE TERMINATION AND MONITOR USB INTERFACE LOGIC IDN RIDN FLT NO FAULT FAULT CT CHARGE TIMER IBUS_DEF CTIMER CEN POR CHARGER DISABLED CHARGER ENABLED INT_3V3 DGND AGND Figure 3. MAX8895W Block Diagram 18 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration MICRO USB-B VBUS BUS_A SYS_A BUS_B SYS_B CBUS CSYS BAT_A RD+ D+ RDD- BAT_B D+ CBAT MAX8895V D- MAX8895X GND 1-CELL Li+ THM RTB RWU SUS_EN RTP RTS INT_3V3 CINT_3V3 ENU_EN RT KB_TM STDBY ISET RISET CEN IDN CHG PREQ RIDN UOK FLT CT CCT DGND AGND Figure 4. MAX8895V/MAX8895X Typical Application Circuit NAME VALUE FUNCTION CBUS 10FF, 16V Decoupling of input supply. CSYS 10FF, 6.3V Decoupling of system rail. CBAT 10FF, 6.3V Decoupling of battery rail. RT User dependent Thermistor for thermal sensing. See the Thermistor Input (THM) section for details. RTB, RTP, RTS User dependent Bias resistors for thermal sensing. See the Thermistor Input (THM) section for details. CINT_3V3 0.1FF, 6.3V CCT 1000pF to 0.2FF RISET RIDN Decoupling of internal 3.3V rail. Capacitor to set charge timer, optional. See the Fault Output (FLT) and Charge Timer (CT) section for details. 1.875kI to 30kI Resistor to set maximum charging current, optional. 15kI to 240kI Resistor to set termination current for charger, optional. RD+, RD- Maxim Integrated 33I D+/D- serial impedance. 19 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration MICRO USB-B VBUS BUS_A SYS_A BUS_B SYS_B CBUS CSYS MAX8895Y BAT_A RD+ D+ BAT_B D+ CBAT RDD- 1-CELL Li+ D- GND THM RWU RTB KB_TM STDBY RTP RTS INT_3V3 CINT_3V3 CEN RT XIN CXTAL_IN ISET XTAL RISET XOUT CXTAL_OUT IDN CHG RIDN PREQ UOK CT CCT FLT DGND AGND Figure 5. MAX8895Y Typical Application Circuit NAME VALUE CBUS 10FF, 16V Decoupling of input supply. CSYS 10FF, 6.3V Decoupling of system rail. 10FF, 6.3V Decoupling of battery rail. CBAT RT FUNCTION User dependent Thermistor for thermal sensing. See the Thermistor Input (THM) section for details. RTB, RTP, RTS User dependent Bias resistors for thermal sensing. See the Thermistor Input (THM) section for details. CINT_3V3 XTAL CXTAL_IN CXTAL_OUT CCT RISET RIDN RD+, RD20 0.1FF, 6.3V Decoupling of internal 3.3V rail. 12MHz 2500ppm MAX8895Y only, clock source for full-speed mode, requires a 2500ppm or better accuracy. User dependent MAX8895Y only, crystal load capacitor, only required for full-speed operation. See the External Crystal/Ceramic Resonator section for details. User dependent MAX8895Y only, crystal load capacitor, only required for full-speed operation. 1000pF to 0.2FF Capacitor to set charge timer, optional. See the Fault Output (FLT) and Charge Timer (CT) section for details. 1.875kI to 30kI Resistor to set maximum charging current, optional. 15kI to 240kI Resistor to set termination current for charger, optional. 33I D+/D- serial impedance. Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration MICRO USB-B VBUS BUS_A SYS_A BUS_B SYS_B CBUS CSYS MAX8895W BAT_A RD+ D+ BAT_B D+ CBAT RDD- 1-CELL Li+ D- GND DET_DONE THM SUS_EN ENU_EN RTB RTP RTS INT_3V3 KB_TM CINT_3V3 RTHM STDBY CEN ISET CHG_TYPE RISET IBUS_DEF IDN RIDN UOK CT FLT DGND AGND CCT Figure 6. MAX8895W Typical Application Circuit NAME VALUE FUNCTION CBUS 10FF, 16V Decoupling of input supply. CSYS 10FF, 6.3V Decoupling of system rail. CBAT 10FF, 6.3V Decoupling of battery rail. RTHM User dependent Thermistor for thermal sensing. See the Thermistor Input (THM) section for details. RTB, RTP, RTS User dependent Bias resistors for thermal sensing. See the Thermistor Input (THM) section for details. CINT_3V3 0.1FF, 6.3V CCT 1000pF to 0.2FF RISET RIDN Decoupling of internal 3.3V rail. Capacitor to set charge timer, optional. See the Fault Output (FLT) and Charge Timer (CT) section for details. 1.875kI to 30kI Resistor to set maximum charging current, optional. 15kI to 240kI Resistor to set termination current for charger, optional. RD+, RD- Maxim Integrated 33I D+/D- serial impedance. 21 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration USB Timing Detailed Description The MAX8895_ is an integrated 1-cell Li+ charger with USB enumeration capability. All power switches for charging and switching the load between battery and external power are internal. No external MOSFETS are required. The MAX8895_ makes it possible to negotiate more than 100mA of charging current from a USB host or hub without processor intervention. The MAX8895_ also automatically detects a dedicated charger or USB charger and set the input current limit accordingly. The battery charge current can be set up to 1.85A. Input power not used by the system charges the battery. tRISE 90% 10% Figure 7. USB Rise and Fall Timing The USB controller executes the adapter detection sequence, which consists of detecting the type of adapter that is externally connected and setting the input current limit accordingly. If attached to a USB charger (host or hub) or a USB 2.0 (host or hub), it enumerates as an HID device and negotiates the maximum charging current level (from VBUS_). The MAX8895V/MAX8895W/MAX8895X operate in lowspeed mode, using an internal 6MHz oscillator, and does not require an external crystal to be USB compliant. The MAX8895Y operates in full-speed mode and requires an external 12MHz crystal. According to the USB 2.0 specification, a low-speed device is not allowed to use a standard USB "B" connector. This is why MAX8895_ is available in both a low- and full-speed version. This makes it possible to use a custom or captive cable for low-speed mode using the MAX8895V/MAX8895W/MAX8895X and still be USB compliant. Operating in full-speed mode, using the MAX8895Y allows use of a standard USB "B" connector. Table 1. Adapter Types TEST POINT 3.3 D+ OR DMAX8895V MAX8895W MAX8895X MAX8895Y USB Interface An integrated USB peripheral controller provides autoenumeration for full-speed (MAX8895Y) and low-speed (MAX8895V/MAX8895W/MAX8895X) modes. tFALL CL = 50pF 15kI Figure 8. Load for D+/D- AC Measurements D+ and DThe internal USB full speed (MAX8895Y)/low-speed (MAX8895V/MAX8895W/MAX8895X) transceiver is brought out to the bidirectional data pins D+ and D-. These pins are ESD protected up to Q8kV (HBM). Connect these pins to a USB "B" custom connector through external 33I series resistors. The MAX8895V/ MAX8895X provide an automatic switchable 1.5kI pullup resistor for D-, while the MAX8895Y provides an automatic switchable 1.5kI pullup resistor for D+. Adapter Detection When an adapter is present on VBUS_, the MAX8895_ examines the external device to identify the type of adapter connected. The possible adapter types are: U Dedicated charger U USB charger (host or hub) U USB 2.0 (host or hub) low power U USB 2.0 (host or hub) high power Each of these different devices has different current capability as shown in Table 1. ADAPTER TYPE OUTPUT VOLTAGE OUTPUT CURRENT Dedicated charger 4.75V to 5.25V at ILOAD < 500mA 2.0V to 5.25V for ILOAD R500mA 500mA to 1.85A USB charger 4.75V to 5.25V at ILOAD < 500mA 0 to 5.25V for ILOAD R 500mA 500mA to 900mA for low speed, full speed 500mA to 1.5A for low speed and full speed USB 2.0 low power 4.25V to 5.25V 100mA (max) USB 2.0 high power 4.75V to 5.25V 500mA (max) 22 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration When an adapter is connected to the MAX8895_, a series of tests is performed to identify the type of device connected. The sequence is done according to the flow charts in Figures 7 and 8. Figures 9, 10, and 11 show the adapter-type detection timing. USB_OK = LOW FROM ANY CONDITION USB_OK = LOW FROM ANY CONDITION DISABLE VDP_SRC DISABLE VDM_SINK DISABLE DM_PU DISABLE I_DM_PD DISABLE DP_CD_PU DISABLE VDP_SRC DISABLE VDM_SINK DISABLE DM_PU DISABLE I_DM_PD DISABLE DP_CD_PU USB_OK = HIGH USB_OK = HIGH NO YES YES DEBOUNCE tUSB_DB DEBOUNCE tUSB_DB YES YES DISABLE VDP_SRC DISABLE VDM_SINK DISABLE DM_PU DISABLE I_DM_PD DISABLE DP_CD_PU ILIM = ISUS STDBY = HIGH FROM ANY CONDITION, USB_OK = _HIGH STDBY = HIGH DISABLE VDP_SRC DISABLE VDM_SINK DISABLE DM_PU DISABLE I_DM_PD DISABLE DP_CD_PU ILIM = ISUS STDBY = HIGH FROM ANY CONDITION, USB_OK = _HIGH YES NO ENU_EN = HIGH YES STDBY = HIGH ILIM = IUSB_LP ENU_EN = HIGH DISABLE I_DP_PD DISABLE DP_CD_PU ENABLE DM_PU ILIM = IUSS_CHG DISABLE DP_PU ILIM = ISUS DELAY tFAULT NO VDAT_REF P VDM < VDM_IH YES NO YES ENUMERATION SUCCEEDED NO DISABLE DM_PU ILIM = ISUS DELAY tFAULT NO DISABLE I_DP_PD DISABLE DP_CD_PU ENABLE DM_PU ILIM = IUSS_CHG YES ILIM = IDCHG ILIM = USB_LP OR USB_HP NO YES DISABLE DP_PU ILIM = ISUS DELAY tFAULT USB SUSPEND? YES YES NO DM > VDM_IH YES ENUMERATION SUCCEEDED ENUMERATION SUCCEEDED NO SUS_EN = LOW NO ILIM = ISUS ILIM = ISUS CHARGE DONE YES YES CHARGE DONE DELAY tRWU INITIATE RESUME YES NO RWU SUPPORTED BY HOST RWU = LOW NO YES NO RWU = LOW USB HOST D- HIGH TO LOW TRANSITION NO NO YES USB SUSPEND? YES YES NO DELAY tRWU INITIATE RESUME DISABLE DM_PU ILIM = ISUS DELAY tFAULT ILIM = USB_LP OR USB_HP NO USB HOST D- HIGH TO LOW TRANSITION NO YES ILIM = IDCHG ILIM = IUSB_CHG SUS_EN = LOW NO DISABLE VDP_SRC DISABLE VDM_SINK ILIM = IENU DELAY tDP_SRC_HC ENABLE DM_PU YES YES ILIM = IUSB_CHG VDAT_REF P VDM < VDM_IH DISABLE VDP_SRC DISABLE VDM_SINK ENABLE I_DM_PD ENABLE DP_CD_PU DELAY tDP_SRC_HC DISABLE VDP_SRC DISABLE VDM_SINK ILIM = IENU DELAY tDP_SRC_HC ENABLE DM_PU ENUMERATION SUCCEEDED NO YES DELAY tRE_ENUM Figure 9. MAX8895X Flow Chart for Adapter Type Detection Maxim Integrated ILIM = IUSB_LP ENABLE VDP_SRC ENABLE VDM_SINK DELAY tDP_SRC_ON DISABLE VDP_SRC DISABLE VDM_SINK ENABLE I_DM_PD ENABLE DP_CD_PU DELAY tDP_SRC_HC DM > VDM_IH YES NO NO NO YES NO ENABLE VDP_SRC ENABLE VDM_SINK DELAY tDP_SRC_ON YES NO YES RWU SUPPORTED BY HOST NO DELAY tRE_ENUM Figure 10. MAX8895V Flow Chart for Adapter Type Detection 23 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration USB_OK = LOW FROM ANY CONDITION DISABLE VDP_SRC DISABLE VDM_SINK DISABLE DP_PU DISABLE I_DM_PD DISABLE DP_CD_PU USB_OK = HIGH NO YES DEBOUNCE tUSB_DB YES DISABLE VDP_SRC DISABLE VDM_SINK DISABLE DP_PU DISABLE I_DM_PD DISABLE DP_CD_PU ILIM = ISUS STDBY = HIGH FROM ANY CONDITION, USB_OK = _HIGH STDBY = HIGH YES NO ENU_EN = HIGH YES ILIM = IUSB_LP NO ENABLE VDP_SRC ENABLE VDM_SINK DELAY tDP_SRC_ON YES VDAT_REF P VDM < VDM_IH DISABLE VDP_SRC DISABLE VDM_SINK ENABLE I_DM_PD ENABLE DP_CDC_PU DELAY tDP_SRC_HC NO DM > VDM_IH DISABLE I_DP_PD DISABLE DP_CD_PU ENABLE DP_PU ILIM = IUSS_CHG DISABLE DP_PU ILIM = ISUS DELAY tFAULT NO NO DISABLE VDP_SRC DISABLE VDM_SINK ILIM = IENU DELAY tDP_SRC_HC ENABLE DP_PU YES ENUMERATION SUCCEEDED NO DISABLE DP_PU ILIM = ISUS DELAY tFAULT YES ILIM = IDCHQ ILIM = USB_LP OR USB_HP ENUMERATION SUCCEEDED NO USB SUSPEND? YES YES ILIM = IUSB_CHG YES SUS_EN = LOW NO ILIM = ISUS YES USB HOST D+ HIGH TO LOW TRANSITION NO CHARGE DONE YES NO DELAY tRWU INITIATE RESUME YES RWU SUPPORTED BY HOST NO RWU = LOW NO YES DELAY tRE_ENUM Figure 11. MAX8895Y Flow Chart for Adapter Type Detection 24 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration USB_OK = LOW FROM ANY CONDITION DISABLE VDP_SRC DISABLE VDM_SINK DISABLE DM_PU DISABLE I_DM_PD DISABLE DP_CD_PU NO USB_OK = HIGH YES DEBOUNCE tUSB_DB YES DISABLE VDP_SRC DISABLE VDM_SINK DISABLE DP_PU DISABLE I_DM_PD DISABLE DP_CD_PU ILIM = ISUS DET DONE = 1 STDBY = HIGH FROM ANY CONDITION, USB_OK = _HIGH STDBY = HIGH YES NO ENABLE VDP_SRC ENABLE VDM_SINK DELAY tDP_SRC_ON YES NO DM = VDAT_REF DISABLE VDP_SRC DISABLE VDM_SINK ENABLE I_DM_PD ENABLE DP_CDC_PU DELAY tDP_SRC_HC NO DISABLE I_DP_PD DISABLE DP_CD_PU ENABLE DM_PU ILIM = IUSB_CHG DET_DONE = 0 IBUS_DEF = 1 DM > VDM_IH DISABLE VDP_SRC DISABLE VDM_SINK ILIM = IENU DELAY tDP_SRC_HC ENABLE DP_PU YES ILIM = VIBUS_DEF NO ENU_EN = LOW YES ILIM = IDCHG DET_DONE = 0 IBUS_DEF = 1 ENUMERATION SUCCEEDED NO DISABLE DM_PU ILIM = ISUS DELAY tFAULT YES DISABLE DM_PU ILIM = ISUS DELAY tFAULT NO DET_DONE = 0 ENUMERATION SUCCEEDED ILIM = USB_LP or USB_HP YES ILIM = IUSB_CHG NO USB SUSPEND? YES YES SUS_EN = LOW NO ILIM = ISUS DET_DONE = 0 USB HOST D+ HIGH TO LOW TRANSITION YES NO CHARGE DONE YES NO DELAY tRWU INITIATE RESUME YES RWU SUPPORTED BY HOST? Figure 12. MAX8895W Flow Chart for Adapter Type Detection Maxim Integrated 25 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration ENUMERATION INITIATED ILIM = 500mA SEND CONNECT YES NO t < tENUM IC IS IN CONFIGURED STATUS NO YES YES DISABLE DM_PU (MAX8895V/MAX8895W/ MAX8895X) DP_PU (MAX8895Y) ENUM_500mA DELAY tENU_FAULT ILIM = 100mA ENABLE DM_PU (MAX8895V/MAX8895W/ MAX8895X) DP_PU (MAX8895Y) NO t < tENUM YES DISABLE DM_PU DELAY tENU_FAULT IC IS IN CONFIGURED STATUS YES ENUM_100mA RETURN TO MAIN LOOP Figure 13. Flow Chart for Enumeration Process MAX8895Y. In this mode, the D+ and D- lines become high impedance. When STDBY is high, VSYS_ is regulated to 50mV (typ) below VBAT_. USB Suspend According to the USB rev 2.0 specification, when a USB host stops sending traffic for at least 10ms to a peripheral (MAX8895_), the peripheral must enter a power-down state called SUSPEND. Once suspended, the peripheral must have enough of its internal logic active to recognize when the host resumes signaling, or if enabled, for generating remote wake-up. The MAX8895_ enters SUSPEND state in two ways: U MAX8895V/MAX8895W/MAX8895X: When no activity is present on D+/D- for 10ms (max), the MAX8895V/ MAX8895W/MAX8895X automatically enters suspend mode to be compliant with USB specification. The MAX8895V/MAX8895W/MAX8895X only enters suspend mode if SUS_EN is pulled high. When entering suspend mode the MAX8895V/MAX8895W/ MAX8895X disables the charger as well as VSYS_ to reduce the input current drawn from VBUS_. The current drawn in this mode is less than 500FA for the MAX8895V/MAX8895W/MAX8895X, ensuring that the device is compliant with USB specification. In suspend state the bus is IDLE: D+ is low and D- is kept high by the MAX8895V/MAX8895W/MAX8895X pullup resistor. When in suspend mode, VSYS_ is powered from VBAT_. When entering automatic suspend mode, the FLT output is pulled low as an indication that the charger is disabled. Once the type of adapter is determined, the MAX8895_ determines the maximum input current limit, if the external adapter is recognized as a USB charger or USB 2.0 device. The MAX8895_ then initiates enumeration and determine the maximum input current limit according to Figure 13. U MAX8895Y: When no activity is present on D+/D- for 10ms (max), the MAX8895Y automatically enters suspend mode to be compliant with USB specification. When entering suspend mode, the MAX8895Y disables the charger as well as VSYS_ to reduce the input current drawn from VBUS_. The current drawn in this mode is less than 2.5mA, ensuring that the device is compliant with the USB specification. Low-Power Mode Driving STDBY high disables the charger as well as VSYS_, to reduce the input current drawn from VBUS_. The current drawn in this mode is less than 500FA for the MAX8895V/MAX8895W/MAX8895X and 2.5mA for the In suspend state, the bus is IDLE: D- is low and D+ is kept high by the MAX8895Y pullup resistor. When in suspend mode, VSYS_ is powered from VBAT_. When entering automatic suspend mode, the FLT output is pulled low as an indication that the charger is disabled. 26 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration VBUS_ DEDICATED CHARGER 1800mA USB CHARGER 1500mA 0.5mA INPUT CURRENT LIMIT 0mA tDP_SRC_ON ON VDP_SRC CHARGER (MAX8895V MAX8895X) IDM_SINK DM_PU D- OFF ON OFF ON OFF LOGIC-HIGH DEDICATED CHARGER USB CHARGER DEDICATED CHARGER OR USB CHARGER LOGIC-LOW tDP_SRC_HC VFLT LOGIC-HIGH LOGIC-LOW Figure 14a. Charger Detection Timing Diagram (MAX8895V/MAX8895X) VBUS_ 500mA 100mA INPUT CURRENT LIMIT 0.5mA 0mA VDP_SRC USB 2.0 (MAX8895V MAX8895X) USB 2.0 HIGH POWER USB 2.0 LOW POWER tDP_SRC_ON ON OFF ON IDM_SINK OFF ON DM_PU D- OFF LOGIC-HIGH LOGIC-LOW VFLT LOGIC-HIGH LOGIC-LOW Figure 14b. USB Detection Timing Diagram (MAX8895V/MAX8895X) Maxim Integrated 27 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration VBUS_ 1800mA 1500mA 0.5mA INPUT CURRENT LIMIT 0mA DEDICATED CHARGER USB CHARGER tDP_SRC_ON ON VDP_SRC CHARGER (MAX8895Y) IDM_SINK DP_PU D- OFF ON OFF ON OFF LOGIC-HIGH DEDICATED CHARGER USB CHARGER DEDICATED CHARGER OR USB CHARGER LOGIC-LOW tDP_SRC_HC LOGIC-HIGH VFLT LOGIC-LOW Figure 15a. Charger Detection Timing Diagram (MAX8895Y) VBUS_ 500mA 100mA INPUT CURRENT LIMIT 0.5mA 0mA VDP_SRC USB 2.0 (MAX8895Y) USB 2.0 HIGH POWER USB 2.0 LOW POWER tDP_SRC_ON ON OFF ON IDM_SINK OFF ON DP_PU D- OFF LOGIC-HIGH LOGIC-LOW VFLT LOGIC-HIGH LOGIC-LOW Figure 15b. USB Detection Timing Diagram (MAX8895Y) 28 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration VBUS 1800mA 1500mA 0.5mA INPUT CURRENT LIMIT 0mA tDP_SRC_ON ON VDP_SRC VDM_SINK DM_PU D- OFF ON OFF ON OFF LOGIC-HIGH LOGIC-LOW tDP_SRC_CON LOGIC-HIGH DET_DONE LOGIC-LOW LOGIC-HIGH IBUS_DEF LOGIC-LOW Figure 16a. Charger Detection Timing Diagram (MAX8895W) VBUS 500mA 100mA 0.5mA INPUT CURRENT LIMIT 0mA USB 2.0 HIGH POWER USB 2.0 LOW POWER tDP_SRC_ON ON VDP_SRC VDM_SINK DM_PU D+ OFF ON OFF ON OFF LOGIC-HIGH LOGIC-LOW LOGIC-HIGH DET_DONE tDP_SRC_CON LOGIC-LOW LOGIC-HIGH IBUS_DEF LOGIC-LOW Figure 16b. USB Detection Timing Diagram (MAX8895W) Maxim Integrated 29 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Wake-Up and USB Resume The MAX8895_ can wake up four ways while in suspend mode: U Logic-high to logic-low transition of STDBY initiating enumeration. U MAX8895V/MAX8895W/MAX8895X: If STDBY is logic-low and SUS_EN is logic-high, the MAX8895V/ MAX8895W/MAX8895X monitor the bus activity on the D- line. If the host resumes bus activity, the MAX8895V/MAX8895W/MAX8895X detects this as a 1 to 0 transition on D-. Once this occurs, the device restarts the oscillator and waits for it to stabilize. U MAX8895Y: If STDBY is logic-low, the MAX8895Y monitors the bus activity on the D+ line. If the host resumes bus activity, the MAX8895Y detects this as a 1 to 0 transition on D+. Once this occurs, the device restarts the oscillator and waits for it to stabilize. Enumeration is started on the MAX8895V/MAX8895W/ MAX8895X only if ENU_EN is logic-low. If ENU_EN is logic-high, the MAX8895V/MAX8895W/MAX8895X does not connect a pullup resistor between D- and INT_3V3, and the current limit is set to 100mA regardless of the input type. When the USB 2.0 host/hub or USB charger detects a plugged-in peripheral (MAX8895_), it interrogates the peripheral to learn about its capabilities and requirements; and if all is well, configures it to bring it on line. This process is known as enumeration. During enumeration the host sends multiple requests to the device (MAX8895_) asking for descriptors (see Table 2) that define the device operation. All the enumeration tasks are self-managed by the MAX8895_ serial interface engine (SIE) without any processor intervention. U Remote wake-up is supported by the MAX8895V/ MAX8895X/MAX8895Y, but the remote wake-up feature must be enabled by the host during the enumeration process. Once suspended, the MAX8895V/ MAX8895X/MAX8895Y look at the state of the battery charger. If the charger is not in the done state, the MAX8895V/MAX8895X/MAX8895Y initiate a remote wake-up signal. If the charger is in the done state, a remote wake-up is not initiated before the charger is restarted due to a drop in battery voltage. The SIE supports the following features: U When the MAX8895V/MAX8895X/MAX8895Y initiate a remote wake-up, they first restart the oscillator and wait for the oscillator to stabilize, and then send the remote wake-up event to signal to the host that it needs to be driven out of the suspend status. U 8 bytes end-point zero (control end point) U If RWU is connected to ground and the remote wake-up feature has not been set by the host during enumeration, the IC waits tRE_ENUM after entering suspend mode, then disconnects the pullup resistor and reinitiates the charger type detection. At the end of enumeration (if successful), the device is ready to transfer data (if needed) and enabled to sink the negotiated current from VBUS_. Enumeration USB bus enumeration is an activity that identifies and assigns unique addresses to devices attached to the bus. Once the MAX8895_ detects VBUS_ is valid for TUSB_DB, the MAX8895_ initiates the detection process to determine the type of device that it is connected to. If the device type is a USB 2.0 host/hub or USB charger, a 1.5kI pullup resistor is connected between D(MAX8895V/MAX8895W/MAX8895X) or D+ (MAX8895Y) to INT_3V3. 30 U USB 2.0 low-speed (1.5Mbps): the MAX8895V/ MAX8895W/MAX8895X pulls D- high to indicate to the host that it is a low-speed device U Full-speed (12Mbps) operation: the MAX8895Y pulls D+ high to indicate to the host that it is a full-speed device U Human interface device (HID) in the consumer page (MAX8895_ does not require any custom drivers) U 1 byte end-point one (INT-IN end point) U USB suspend/resume support U Remote wake-up capability Figure 17 shows USB bus traffic as captured by a CATC USB bus analyzer. The traces show a PC (host) enumerating the peripheral (MAX8895V/MAX8895W/ MAX8895X). Notice that the LS field indicates the low-speed (1.5Mbps) operation of the MAX8895V/ MAX8895W/MAX8895X. 1) The host uses the default CONTROL end-point EP0 (shown in the "ENDP" boxes) to send a request to the device. The host initially sends requests to address 0 (shown in the ADDR boxes) to communicate with a device to which it has not yet assigned a unique address. Maxim Integrated RESET Maxim Integrated INTERRUPT IN INTERRUPT IN L S L S 19 TRANSFER 20 IN TRANSFER INTERRUPT L S 18 IN TRANSFER INTERRUPT L S 17 IN TRANSFER INTERRUPT L S 16 IN TRANSFER INTERRUPT L S 15 GET TRANSFER CONTROL L S 14 SET TRANSFER CONTROL L S 13 SET TRANSFER CONTROL L S 12 GET TRANSFER CONTROL L S 11 GET TRANSFER CONTROL L S 10 GET TRANSFER CONTROL L S 9 GET TRANSFER CONTROL L S 8 GET TRANSFER CONTROL L S 7 GET TRANSFER CONTROL L S 6 GET TRANSFER CONTROL L S 5 GET TRANSFER CONTROL L S 4 GET TRANSFER CONTROL L S 3 GET TRANSFER CONTROL L S 2 SET TRANSFER CONTROL L S 3 ADDR 3 ADDR 3 ADDR 3 ADDR 3 ADDR 3 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 0 ADDR 25.881ms 1 _> TRANSFER DIR 69 GET 0 PACKET CONTROL L S TRANSFER 1 ENDP 1 ENDP 1 ENDP 1 ENDP 1 ENDP 1 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP 0 ENDP bREQUEST wVALUE wVALUE DEVICE TYPE bREQUEST GET_DESCRIPTOR DESCRIPTORS bREQUEST DESCRIPTORS bREQUEST 0x0000 wVALUE 0x0000 wINDEX 0 wLENGTH TIME TIME 7.991ms 1 1 BYTES TRANSFERRED TIME 8.009ms BYTES TRANSFERRED TIME 8.000ms 1 1 BYTES TRANSFERRED TIME 8.000ms BYTES TRANSFERRED TIME 7.991ms 1 8.009ms BYTES TRANSFERRED 1 BYTES TRANSFERRED 00002.4777 4843 TIME STAMP 00002.4713 4307 TIME STAMP 00002.4649 4323 TIME STAMP 00002.4585 4339 TIME STAMP 00002.4421 4899 TIME STAMP 00002.4457 4371 TIME STAMP wVALUE 0x0A bREQUEST REPORT_DESCRIPTOR TYPE I R bREQUEST C 0x0000 wINDEX GET_DESCRIPTOR Tp D H_>D wVALUE NEW CONFIGURATION 1 bREQUEST SET_CONFIGURATION CONFIGURATION TYPE, INDEX O wVALUE wVALUE CONFIGURATION TYPE, INDEX O 0x0000 wINDEX 0x08 STALL 0 wLENGTH 0x0000 wINDEX 0x0000 wINDEX DEVICE DESCRIPTOR bREQUEST 0x0000 wINDEX wINDEX LANGUAGE ID 0x0409 GET_DESCRIPTOR wVALUE DEVICE TYPE bREQUEST GET_DESCRIPTOR wVALUE STRING TYPE, INDEX 1 bREQUEST GET_DESCRIPTOR GET_DESCRIPTOR wINDEX LANGUAGE ID 0x0409 STRING TYPE, LANGID CODES REQUESTED wVALUE wVALUE STRING TYPE, INDEX 1 bREQUEST GET_DESCRIPTOR GET_DESCRIPTOR 0x0000 wINDEX 0x0000 wINDEX STRING TYPE, LANGID CODES, REQUESTED wVALUE wVALUE CONFIGURATION TYPE, INDEX O bREQUEST bREQUEST TIME 46.999ms DEVICE DESCRIPTOR 0 wLENGTH GET_DESCRIPTOR GET_DESCRIPTOR DESCRIPTORS DEVICE DESCRIPTOR CONFIGURATION TYPE, INDEX O wVALUE 0x0000 wINDEX 0x0000 wINDEX 0x0000 wINDEX GET_DESCRIPTOR bREQUEST NEW ADDRESS 3 wVALUE 00002.2722 1739 TIME STAMP DEVICE TYPE SET_ADDRESS bREQUEST 52.919ms TIME GET_DESCRIPTOR TIME TIME STAMP 00002.3521 4587 TIME STAMP 00002.2673 4787 TIME TIME REPORT DESCRIPTOR DESCRIPTORS 3.000ms TIME 18.999ms TIME 4 DESCRIPTORS DESCRIPTORS 15.000ms TIME 00002.4313 4403 TIME STAMP 00002.4161 4435 TIME STAMP 8.000ms TIME CONFIGURATION DESCRIPTOR 00002.4009 5299 TIME STAMP 11.013 ms TIME TIME STAMP TIME TIME STAMP 5.000ms TIME 00002.3921 4491 TIME STAMP 5.000ms TIME 00002.3817 4515 TIME STAMP 5.000ms TIME STAMP 00002.4057 4459 TIME STAMP 00002.3881 4499 TIME STAMP 00002.3777 4539 TIME STAMP 00002.3569 4579 00002.4337 4395 TIME STAMP 00002.4097 4451 LANG SUPPORTED DESCRIPTORS 8.000ms TIME 5.000ms 00002.3609 4563 LANG SUPPORTED DESCRIPTORS 21.000ms DESCRIPTORS 5.986ms TIME USB CHARGER DESCRIPTORS LANGUAGE ID 0x0000 wINDEX USB CHARGER DESCRIPTORS LANGUAGE ID 0x0000 wINDEX 4 DESCRIPTORS DESCRIPTORS CONFIGURATION DESCRIPTOR DESCRIPTORS 6.000ms TIME 00002.3145 4675 TIME STAMP 6.80ms MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Figure 17. USB Bus Traffic: MAX8895V/MAX8895W/MAX8895X Enumeration 31 32 SET CONTROL SET CONTROL F S 1 TRANSFER 1 0 bREQUEST GET_DESCRIPTOR ENDP 0 ENDP ADDR 1 CONTROL GET F S INTERRUPT IN F S TRANSFER 19 1 ENDP ADDR 1 1 1 ENDP IN 18 ADDR INTERRUPT F S TRANSFER BYTES TRANSFERRED 1 1 BYTES TRANSFERRED 1 BYTES TRANSFERRED 1 1 IN 17 ENDP ADDR INTERRUPT F S TRANSFER 1 1 IN 16 BYTES TRANSFERRED 1 ADDR INTERRUPT F S TRANSFER 0x0000 wVALUE TRANSFER 15 0x0A bREQUEST 0 1 SET ENDP ADDR CONTROL F S 14 1 SET TRANSFER bREQUEST SET_CONFIGURATION 0 ADDR CONTROL F S GET_DESCRIPTOR 13 0 1 GET TRANSFER ENDP ADDR CONTROL bREQUEST bREQUEST GET_DESCRIPTOR ENDP 0 1 bREQUEST GET_DESCRIPTOR ENDP 1 bREQUEST GET_DESCRIPTOR bREQUEST 0 F wINDEX wVALUE wVALUE wVALUE wVALUE 0x0000 wINDEX TIME 32.001ms TIME wVALUE TIME 3.000ms DESCRIPTOR TYPE 0x22, INDEX 0 0x78 STALL NEW CONFIGURATION 1 wVALUE CONFIGURATION TYPE wVALUE CONFIGURATION TYPE, INDEX O 32.001ms TIME 0ns wVALUE STRING TYPE, INDEX 1 32.001ms DESCRIPTORS 0x0000 wINDEX 0x0000 wINDEX wINDEX 0x0000 wINDEX 20.001ms TIME 0x0000 wINDEX 0x0000 wINDEX TIME DESCRIPT0RS 6.001ms TIME STRING: USB CHARGER DESCRIPTORS LANGUAGE ID 0x0000 wINDEX STRING: USB CHARGER DESCRIPT0RS LANGUAGE ID 0x0000 wINDEX 3.001ms TIME 9.000ms DESCRIPTORS 8.000ms HIDM REPORT DESCRIPTOR 4 DESCRIPTORS TIME CONFIGURATION TYPE, INDEX O 0x78 DESCRIPT0RS DEVICE DESCRIPTOR DESCRIPT0RS LANGUAGE ID 0x0409 DESCRIPT0RS STALL 4 DESCRIPTORS LANGUAGE ID 0x0409 wINDEX 0x0000 wINDEX TIME 6.000ms CONFIGURATION DESCRIPTOR DESCRIPT0RS DEVICE DESCRIPTOR STRING TYPE, LANGID CODES REQUESTED DEVICE TYPE TIME 0x0000 DESCRIPTORS DEVICE DESCRIPTOR STRING TYPE. LANGID CODES REQUESTED wVALUE DESCRIPTOR TYPE 0X06, INDEX 0 wVALUE CONFIGURATION TYPE wVALUE CONFIGURATION TYPE 0x0000 wINDEX wVALUE ENDP S wVALUE DEVICE TYPE TIME 47.002ms STRING TYPE, INDEX 1 ADDR ADDR wVALUE NEW ADDRESS 1 0x0000 wINDEX bREQUEST 6627 IDLE wVALUE DEVICE TYPE GET_DESCRIPTOR GET_DESCRIPTOR bREQUEST GET_DESCRIPTOR bREQUEST GET_DESCRIPTOR bREQUEST GET_DESCRIPTOR bREQUEST GET_DESCRIPTOR bREQUEST SET_ADDRESS bREQUEST 26.370ms GET_DESCRIPTOR 12 GET bREQUEST GET_DESCRIPTOR 0 ENDP 0 TRANSFER CONTROL F S 11 GET TRANSFER CONTROL F S 10 1 GET TRANSFER ADDR CONTROL F S 9 1 GET 8 TRANSFER ADDR CONTROL F S TRANSFER 1 GET ENDP ADDR CONTROL F 0 S ENDP 1 0 ENDP 0 ENDP ADDR 7 GET TRANSFER CONTROL F S 6 1 GET TRANSFER ADDR CONTROL F S 5 1 GET TRANSFER ADDR CONTROL F 0 S ENDP 1 0 ADDR 4 GET 1 ENDP 0 0 ADDR ENDP 0 ENDP ADDR 0 ADDR TRANSFER CONTROL F S 3 2 TRANSFER GET F S TRANSFER RESET CONTROL F S TRANSFER TIME TIME 8.000ms TIME 16.001ms TIME 30.001ms 8.000ms TIME 0x0409 DESCRIPT0RS 0x0409 DESCRIPT0RS 5.000ms TIME 5.001ms TIME 5.000ms MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Figure 18. USB Bus Traffic: MAX8895Y Enumeration Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration 2) The host begins by sending a Get_Descriptor_Device request (Transfer 0 in Figure 16). It does this to determine the maxPacketSize of the device's EP0 buffer (for the MAX8895V/MAX8895X, it is 8 bytes). The host then resets the device by issuing a bus reset (packet 69). 3) In transfer 1, the host assigns a unique address to the peripheral by using the Set_Address request. The assigned address depends on how many other USB devices are currently attached to the host. In this case, the address assigned to our peripheral device (MAX8895V/MAX8895X) is 3. Thereafter, the MAX8895V/MAX8895X respond only to requests directed to address 3. This address remains in force until the host does a bus reset or the device is disconnected. Notice that the peripheral address field (ADDR) in the bus trace changes from 0 to 3 after transfer 1. 4) In transfers 2 to 11, the host asks for various descriptors. The device FSM needs to determine from the eight setup bytes which descriptor to send, use this information to access one of several character arrays (ROMs) representing the descriptor arrays. 5) In transfer 12, the host requests the device to use the specified configuration (1) and the device enters the configured state. According to the USB 2.0 specification, a bus powered device can be either low power (it may draw no more than 100mA) or high power (it may draw no more than 500mA). All devices must default to low power. The transition to high power is under software control (running on the host side). It is the responsibility of software to ensure adequate power is available before allowing devices to consume high-power. The MAX8895_ initiates enumeration by asking for 500mA of current. If the MAX8895_ does not enter configured status before the tENUM (10s, typ), it interprets this as an indication that the host is not able to support the requested current. The MAX8895_ disconnects the pullup resistor on D- (MAX8895V/MAX8895X)/D+ (MAX8895Y), wait for tENU_FAULT, and then retry to enumerate, but now as a low current device (100mA). If the MAX8895_ has still not reached the configured status after tENUM, the MAX8895_ assumes that either the host is nonresponsive or a wrong adapter type is detected. In this case, the MAX8895_ disconnects the pullup resistor on D- (MAX8895V/MAX8895W/MAX8895X)/D+ (MAX8895Y) and wait for tENU_FAULT + tFAULT before starting the adapter detection process again. Figure 18 shows the USB traffic captured during the MAX8895Y enumeration. Notice the field FS indicates the full-speed (12Mbps) operation of the MAX8895Y. Table 2. Device Descriptor LENGTH (bits) OFFSET (bits) DECODED HEXVALUE bLength bDescriptorType bcdUSB bDeviceClass bDeviceSubClass bDeviceProtocol bMaxPacketSize0 idVendor* idProduct* bcdDevice 8 8 16 8 8 8 8 16 16 16 0 8 16 32 40 48 56 64 80 96 0x12 0x01 0x0200 0x00 0x00 0x00 0x08 -- 0x5346 0x1234 0x12 0x01 0x0200 0x00 0x00 0x00 0x08 -- 0x5346 0x1234 iManufacturer 8 112 0x00 0x00 iProduct 8 120 0x01 0x01 The product stringed descriptor index is 1 iSerialNumber 8 128 0x00 0x00 The device does not have the string descriptor describing the serial number bNumConfigurations 8 136 0x01 0x01 The device has 1 possible configuration FIELD Maxim Integrated DESCRIPTION Descriptor size is 18 bytes Device descriptor type Device compliant to the USB specification version 2.0 Each interface specifies its own class information Each interface specifies its own subclass information No protocols the device basis Maximum packet size for end-point zero is 8 Vendor ID is 2922: Maxim Integrated Products Product ID is 21318 The device release number is 1.00 The device does not have the string descriptor describing the manufacturer 33 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Smart Power Selector The Smart Power Selector seamlessly distributes power between the external VBUS_ input, the battery (VBAT_), and the system load (VSYS_). See Figure 19. The Smart Power Selector basic functions are: U With both an external adapter and battery connected: a. When the system load requirements are less than the input current limit, the battery is charged with residual power from the input. b. When the system load requirements exceed the input current limit, the battery supplies supplemental current to the load. U When the battery is connected and there is no external power input, the system is powered from the battery. U When an external power input is connected and there is no battery, the system is powered from VBUS_. If the junction temperature starts to get too hot (+110NC typ), the charging rate is reduced. If this is not sufficient to cool down the MAX8895_, the input current limit is then reduced. System Load Switch An internal 55mI (typ) MOSFET connects VSYS_ to VBAT_ (Q2, Figure 19) when no voltage source is available at VBUS_ and VBAT_ is above the battery UVLO threshold. When an external source is detected at VBUS_, this switch controls the charging of VBAT_ and VSYS_ is powered from the valid input source through the input current limiter. The VSYS_ - VBAT_ switch also prevents VSYS_ from falling below VBAT_ when the system load exceeds the input current limit. If that should happen, VSYS_ is allowed to drop to VBAT_. At this point, the VSYS_ - VBAT_ switch turns on so that the battery supplies additional ISYS_ load current. If the system load continuously exceeds the input current limit, then the battery does not charge, even though external power is connected. This is not expected to occur in most cases, since high loads usually occur only in short peaks. During these peaks, battery energy is used, but at all other times the battery charges. Input Limiter The input limiter distributes power from the external adapter to the system load and battery charger. In addition to the input limiter's primary function of passing power to the system and charger, it performs several additional functions to optimize use of available power. U Input Voltage Limiting: If the VBUS_ input voltage is above the overvoltage threshold (VBUS_OVP), the MAX8895_ enters overvoltage lockout (OVL). OVL protects the MAX8895_ and downstream circuitry from high-voltage stress up to 16V at VBUS_. In OVL, VINT_3V3 remains on, the input switch that sees overvoltage (Q1, Figure 19) opens, FLT is pulled low, and UOK, CHG, DET_DONE, and PREQ become high-impedance. In OVL, the charger turns off. The VBAT_ - VSYS_ switch (Q2, Figure 19) closes, allowing the battery to power VSYS_. VBUS_ is also invalid if it is less than VBAT_, or less than the USB undervoltage threshold (VBUS_UVLO_F). With an invalid input voltage, VSYS_ connects to BAT_ through a 55mI (typ) switch (Q2, Figure 19). U Input Overcurrent Protection: The current at VBUS_ is limited to prevent input overload. This current limit is automatically selected to match the capabilities of the adapter source, whether it is a 100mA or 500mA USB 2.0 source, or 500mA to 1.8A for a dedicated adaptor or USB charger. When the load exceeds the input current limit, VSYS_ drops to 50mV (typ) below VBAT_ and the battery supplies supplemental load current. VSYS_ VBUS_ Q1 CHARGE CURRENT LOAD CURRENT Q2 CHARGE AND SYS LOAD SWITCH MAX8895V MAX8895W MAX8895X MAX8895Y SYSTEM LOAD VBAT_ 1-CELL Li+ 3.4V (min) VSYS_ 140mV VBAT_ GND Figure 19. Smart Power Selector Block Diagram 34 *Contact factory for specific vendor ID and product ID. TIME Figure 20. VSYS_ Regulation Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration VBUS_ 440mV (typ) IIILM 140mV (typ) 500mA VSYS_ 3.4V (min) VBAT_ TIME ADAPTER TYPE DETECTION ADAPTIVE INPUT CURRENT-LIMIT REGULATION Figure 21. Adaptive Input Current-Limit Regulation Loop U Thermal Limiting: The MAX8895V/MAX8895X/ MAX8895Y reduce input current by 5%/NC when its die temperature exceeds TDIE_LIM (+110NC typ). The system load (VSYS_) has priority over charger current, so the input current is first reduced by lowering the charge current. If the junction temperature still reaches TDIE_LIM +20NC in spite of charge current reduction, no input VBUS_ current is drawn, the battery supplies the entire system load, and VSYS is regulated at 50mV (typ) below VBAT_. Note: The on-chip thermal limiting circuitry is not related to, and operates independently from, the thermistor input. U Adaptive Battery Charging: While the system is powered from VBUS_, the charger draws power from VSYS_ to charge the battery. If the combined load between the charger and system exceeds the input current limit, an adaptive charger control loop reduces charge current to prevent the VSYS_ voltage from collapsing. Regulation Threshold The MAX8895_ always regulates VSYS_ to 140mV (typ) above VBAT_ with a minimum voltage of 3.4V regardless of what device is connected. The 3.4V minimum voltage regulation reduces the ripple on VSYS_ during peak load conditions where the input current limit is tripped. Maxim Integrated Input Current Limit If the connected adapter is a USB 2.0 device the input current limit is set by default to 100mA. If ENU_EN is connected to INT_3V3 or driven logic-high for the MAX8895V/MAX8895X/MAX8895Y, the charger input current limit remains at 100mA. If ENU_EN is set to logic-high for the MAX8895W the charger's input current limit is determined by the logic state of IBUS_DEF. When ENU_EN is connected to AGND, automatic enumeration is initiated. The MAX8895_ proceeds to determine if the external USB device is a low- or high-power device and set the input current limit to 100mA or 500mA, respectively. For a dedicated charger or USB charger, the current limit is determined by loading the adapter. When the adapter's output voltage starts to collapse, it is an indication that the current limit of the device is reached. The MAX8895_ set the input current limit to regulate VBUS to VSYS +440mV (typ). This ensures that the power dissipation in the MAX8895_ is kept to a minimum, and at the same time, ensuring that the adapter's current capability is fully utilized. When a dedicated charger is detected, the input current limited is limited by the adaptive input current limit. In this mode, it is up to the adapter to limit the maximum current, which is 1.85A for a dedicated charger and 1.5A for a USB charger, according to the USB charging specification. 35 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration If the adapter output (VBUS) starts to drop below VSYS - 440mV (typ), the input current limit function adaptively decreases the input current limit to ensure that the adapter is not overloaded. When the input current limit is reached, the first action taken by the MAX8895_ is to reduce battery charge current. If, after the charge current is reduced to 0mA, the load at ISYS still exceeds the input current limit, VSYS begins to fall. When VSYS drops to 50mV below VBAT, the VSYS - VBAT switch turns on, using battery power to support the system load during the load peak. See Figure 21 for more information. Power Monitor Output (UOK) UOK is an open-drain output that pulls low when the VBUS_ input has valid power. The UOK monitor has several different thresholds, depending on what type of adapter detected. The different thresholds are as follows: U The initial detection threshold allows all types of adapters to be detected on VBUS_. Once the type of adapter is determined, the UVLO threshold is changed. U For any USB 2.0 device the UVLO thresholds are set to be compliant with USB specifications. U For a dedicated charger, the UVLO (falling) threshold is lowered to VSYS_ + 50mV (typ) to allow for supporting collapsing charger types, allowing the MAX8895_ to operate with lower power dissipation. Note that since the VBUS_ UVLO threshold is changed after initial detection of the device type, there are conditions where the MAX8895_ can toggle between VBUS_ valid and not valid. This is an indication that the adapter is not within the specified limits. See Table 3 for more information. Table 3. UOK Monitor Thresholds THRESHOLDS UVLO OVLO (V) Initial VBUS_ detection 4.0V (typ), rising For USB 2.0 low power 3.9V (typ), falling For USB 2.0 high power 4.1V (typ), falling For dedicated charger to USB charger 6.9 VSYS_ + 50mV (typ), falling VCHG_REG VBAT_FCHG_R IFCHG 0.6 x IFCHG ICHG_DONE VBAT_PCHG_R IPCHG PRECHARGE t < tPCHG TOP-OFF FAST-CHARGE t < tFCHG MAINTENANCE CHARGE CHARGE DONE TIME t = tMTCHG Figure 22. Charging States 36 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Soft-Start To prevent input transients that can cause instability in the USB power source, the rate of change of input current and charge current is limited. When a valid USB 2.0 input is connected, the input current limit is ramped from 0 to 100mA in 50Fs. Once enumeration is ended, the current can be ramped to 500mA or to the new input current limit value in 50Fs. NO VALID VBUS UOK = HIGH-Z (CHG = HIGH-Z) FLT = HIGH-Z ICHG = 0mA VBUS_UVLO < VBUS_ < VBUS_OVP When the charger is enabled, the charge current ramps from zero to the final value in 1.5ms (typ). Charge current also ramps when transitioning to fast-charge from prequalification and when changing the USB charge current from 100mA to 500mA. CHARGER OFF UOK = LOW (CHG = HIGH-Z) FLT = LOW ICHG = 0mA PREQUAL U Fast-charge: In fast-charge mode, the charging current is set to maximum IFCHG. The actual charging current is determined by ILIM - ISYS_. U Top-off charge: In top-off mode, the battery voltage has almost reached the set point (VBAT_FCHG_R). The charging current is reduced in this mode to prevent overcharging the battery, and also to minimize the power dissipation in the battery. U Maintenance charge: The charger enters this mode when the charging current has dropped below the ICHG_DONE threshold. The charger continues to charge for tMTCHG time to ensure the battery is fully charged before the charger is disabled. U Charge done: Charger is disabled and only engages again if the battery voltage drops below the VBAT_RECHG threshold. tCHG_TIMER > tPCHG UOK = LOW PREQ = LOW (CHG = LOW) FLT = HIGH-Z ICHG = IPCHG Battery Charger U Precharge: When the battery voltage is below VBAT_PCHG_R. In this state, the battery is charged at maximum IPCHG. If the IPCHG > ILIM, then the precharging current is determined by the ILIM (input current limit). Charging a Li+ battery at high charging current when it is fully discharged can cause the battery to become unstable and potentially dangerous. Charging at high charging rates on a fully discharged battery can also reduce life cycles of the Li+ battery. CEN = HIGH FROM ANY STATE CEN = LOW RESET CHARGE TIMER Note: There is no di/dt limiting if IISET is changed suddenly using a switch at RISET. The battery charger has five different states of operation (see Figures 22 and 23): VBUS_UVLO > VBUS_ OR VBUS_OVP < VBUS_ FROM ANY STATE VBAT_ > VBAT_PCHG_R RESET CHARGE TIMER VBAT_ < VBAT_PCHG_F RESET CHARGE TIMER FAST-CHARGE VBAT_ < VBAT_FCHG_F FAULT tCHG_TIMER > tFCHG UOK = LOW (CHG = LOW) FLT = HIGH-Z *ICHG = IFCHG UOK = LOW (CHG = HIGH-Z) FLT = LOW ICHG = 0mA VBAT_ > VBAT_FCHG_R VBAT_ < VBAT_PCHG_F RESET CHARGE TIMER TOP-OFF CHARGE UOK = LOW (CHG = LOW) FLT = HIGH-Z ICHG = IFCHG/2 ICHG R ICHG_DONE RESET CHARGE TIMER tCHG_TIMER > tFCHG ICHG < ICHG_DONE AND IBUS < ILIM tDIE < tDIE_LIM RESET CHARGE TIMER MAINTENANCE CHARGE UOK = LOW (CHG = HIGH-Z) FLT = HIGH-Z ICHG < ICHG_DONE tCHG_TIMER > tMTCHG VBAT_ > VBAT_RECHG RESET CHARGE TIMER DONE UOK = LOW (CHG = HIGH-Z) FLT = HIGH-Z ICHG = 0mA *CHARGE TIMER SLOWED DOWN BY X2 IF: ICHG < IFCHG/2 AND PAUSED IF: ICHG < IFCHG/5 ( ) MAX8895V/MAX8895X/ MAX8895Y ONLY FROM ANY CHARGING STATE TTHM_COLD < TA < TTHM_HOT TTHM_COLD > TA OR TTHM_HOT < TA TEMPERATURE SUSPENSE UOK = LOW (CHG = HIGH-Z) FLT = HIGH-Z ICHG = 0mA CHARGE TIMER PAUSED Figure 23. Charger Flow Chart Maxim Integrated 37 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Charge Enable (CEN) When CEN is logic-low, the battery charger is enabled. When CEN is logic-high, the battery charger is disabled. CEN does not affect VSYS_. In many systems, there is no need for the system controller (typically a microprocessor) to disable the battery charger because the MAX8895_ Smart Power Selector circuitry independently manages charging and USB-battery power handover. In these situations, CEN may be connected to ground. Setting Charge Current (ISET) ISET adjusts the charge current to match the capacity of the battery. The maximum charging current can be fixed by connecting ISET to INT_3V3 or can be adjusted by connecting ISET to ground through a resistor. When ISET is connected to ground through a resistor the maximum charging current is determined using the following formula: IFCHG = 3000 RISET where RISET is a resistor from ISET to ground. Determine the IFCHG value by considering the characteristics of the battery. It is not necessary to limit charge current based on the capabilities of the expected adapter input, the system load, or thermal limitations of the PCB. The MAX8895_ automatically adjusts the charging algorithm to accommodate these factors. VISET (V) 1.5V Monitoring Charge Current (ISET) In addition to setting charge current, ISET can also be used to monitor the actual current charging the battery. The ISET output voltage is: = I CHG VISET x 2000 RISET where: ICHG is the actual battery charge current, RISET is a resistor from ISET to ground. A 1.5V output indicates the battery is being charged at the maximum fast-charge current (IFCHG). 0V indicates no charging. The ISET voltage is also used by the charger control circuitry to set and monitor the battery current. Avoid adding more than 10pF of capacitance directly to the ISET pin. If filtering of the charge current monitor is necessary, add a resistor of 100kI or more between ISET and the filter capacitor to preserve charger stability. If the maximum charge current (IFCHG), is set to the default value, the current monitor function is not available. Charge Termination (IDN) When the charge current falls to the termination threshold and the charger is in voltage mode, charging is complete. Charging continues for a time period defined by the tCHG_DONE and then enters the DONE state where charging stops. The IDN input adjusts the charge current termination threshold. The termination threshold can be fixed by connecting IDN to INT_3V3 or can be adjusted by connecting IDN to ground through a resistor. When IDN is connected to ground through a resistor, the charge done threshold is determined using the following formula: MONITORING THE BATTERY CHARGE CURRENT USING VISET I TERM = 2400 RIDN where RIDN is a resistor from IDN to ground. 0V BATTERY CHARGE CURRENT (A) 0A DISCHARGE CHARGE = 1.5V x 2000 RISET OR = IFCHG Figure 24. Monitoring Charge Current with the ISET Voltage 38 Note that if charge current falls to ITERM as a result of the input or thermal limiter, the charger does not enter the DONE state. For the charger to enter DONE, charge current must be less than ITERM, the charger must be in voltage mode, and the input or thermal limiter must not be reducing charge current. The charger exits the DONE state and fast-charge resumes if the battery voltage subsequently drops below VBAT_RECHG or if CEN is cycled. Connecting IDN to INT_3V3 selects the default termination current threshold. Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Charge Status Outputs Charge Output (CHG) (MAX8895V/MAX8895X/ MAX8895Y Only) CHG is an active-low, open-drain output that is driven low during charging. CHG is logic-low when the battery charger is in fast-charge and top-off states. When charge current falls to the charge termination threshold and the charger is in voltage mode CHG goes high impedance. CHG holds its current state if the thermistor causes the charger to enter temperature suspend mode. When the MAX8895V/MAX8895X/MAX8895Y are used with a microprocessor, connect a pullup resistor between CHG and the logic I/O voltage to indicate charge status to the microprocessor. Alternatively, CHG can sink up to 20mA for an LED indicator. Prequalification Output (PREQ) (MAX8895V/MAX8895X/MAX8895Y Only) PREQ is an active-low, open-drain output that is driven low when the charger is in prequalification state. When the MAX8895V/MAX8895X/MAX8895Y are used in conjunction with a microprocessor, connect a pullup resistor between PREQ and the logic I/O voltage to indicate charge status to the microprocessor. Alternatively, PREQ can sink up to 20mA for an LED indicator. Fault Output (FLT) and Charge Timer (CT) FLT is an active-low, open-drain output that is driven low during a battery fault. The fault state occurs when either the prequalification or fast-charge timer expires. The prequalification and fast-charge fault timers are set by CCT: t PREQUAL = 16min x t= FCHG 100min x C CT 0.068FF C CT 0.068FF While in fast-charge mode, a large system load or device self-heating may cause the MAX8895_ to reduce charge current. Under these circumstances, the fast-charge timer adjusts to ensure that adequate charge time is still allowed. Consequently, the fast-charge timer is slowed by 2x if charge current is reduced below 50% of the programmed fast charge level. If charge current is reduced to below 20% of the programmed level, the fast-charge timer is paused. The fast-charge timer is not adjusted if the charger is in voltage mode where charge current reduces due to current tapering under normal charging. To exit a fault state, toggle CEN or remove and reconnect the VBUS_ input source. Note: A thermistor out-ofMaxim Integrated range or on-chip thermal limit conditions are not considered faults. When the MAX8895V/MAX8895X/MAX8895Y are used in conjunction with a microprocessor, connect a pullup resistor between FLT and the logic I/O voltage to indicate fault status to the microprocessor. Alternatively, FLT can sink up to 20mA for an LED indicator. CHG_TYPE Output (MAX8895W Only) The output CHG_TYPE is used to indicate the type of interface detected. If CHG_TYPE output is logic level low the input current limit is set to 100mA or less. If CHG_TYPE output is logic level high the input current limit is set to 500mA or greater. DET_DONE Output (MAX8895W Only) DET_DONE is an active low, open-drain output that is driven low once adapter detection is complete. DET_DONE is high impedance in suspend mode. IBUS_DEF Output (MAX8895W Only) The IBUS_DEF input is only valid when ENU_EN is set to logic-high activating the adapter type detection. If the adapter type is detected as a USB 2.0 device, the input current limit is set to the programmed value and the MAX8895W does not initiate USB enumeration. If IBUS_DEF is connected to ground or logic level low, the input current limit is set to 100mA. If IBUS_DEF is connected to INT_3V3 or logic level high, the input current limit is set to 500mA. Thermistor Input (THM) The THM input connects to an external negative temperature coefficient (NTC) thermistor to monitor battery or system temperature. Charging is suspended when the thermistor temperature is out of range. The charge timers are suspended and hold their state, but no fault is indicated. When the thermistor comes back into range, charging resumes and the charge timer continues from where it was at previously. Connecting THM to AGND disables the thermistor monitoring function. Since the thermistor monitoring circuit employs an external bias resistor from THM to VINT_3V3 (RTB, Figure 25), the thermistor is not limited only to 10kI (at TA = +25NC). Any resistance thermistor can be used as long as the value of RTB is equivalent to the thermistor's TA = +25NC resistance. For example, with a 10kI at TA = +25NC thermistor, use 10kI at RTB, and with a 100kI at TA = +25NC thermistor, use 100kI. For a typical 10kI at TA = +25NC thermistor and a 10kI RTB resistor, the charger enters a temperature suspend state when the thermistor resistance falls below 3.97kI (too hot) or rises above 28.7kI (too cold). These limits 39 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration correspond to a 0NC to +50NC range when using a 10kI NTC thermistor with a beta of 3500. The general relation of thermistor resistance to temperature is defined by the following equation: R = T R 25 1 1 - T + 273 298 xe RT = The resistance (I) of the thermistor at temperature T in NC. R25 = The resistance (I) of the thermistor at TA = +25NC. A = The material constant of the thermistor which typically ranges from 3000K to 5000K. T = The temperature of the thermistor in NC. Table 4 shows the MAX8895_ THM temperature limits for different thermistor material constants. where: Table 4. Fault Temperatures for Different Thermistors THERMISTOR (K) RTB (kI) (Figure 22) 3000 3250 3500 3750 4250 10 10 10 10 10 Resistance at +25NC (kI) 10 10 10 10 10 Resistance at +50NC (kI) 4.59 4.30 4.03 3.78 3316 Resistance at 0NC (kI) 36.91 25.14 27.15 29.32 31.66 Nominal hot trip temperature (NC) 55 53 50 49 46 Nominal cold trip temperature (NC) -3 -1 0 2 4.5 CEN MAX8895V MAX8895X MAX8895Y RTB 0.74 x VINT_3V3 ALTERNATE THERMISTOR CONNECTION COLD THERMISTOR CIRCUITRY THM 0.28 x VINT_3V3 RTS HOT RTP 0.03 x VINT_3V3 RT ENABLE THM THM OUT OF RANGE DISABLE CHARGER ALL COMPARATORS 60mV HYSTERESIS RT AGND Figure 25. Thermistor Monitor Circuitry 40 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Some designs may require other thermistor temperature limits. The threshold adjustment can be accommodated by changing RTB, connecting a resistor in series and/or in parallel with the thermistor, or using a thermistor with different A. For example, a TA = +45NC hot threshold and TA = 0NC cold threshold can be realized by using a thermistor with a A of 4250 and connecting a 120kI resistor in parallel. Since the thermistor resistance near TA = 0NC is much higher than it is near TA = +50NC, a large parallel resistance lowers the cold threshold, while only slightly lowering the hot threshold. Conversely, a small-series resistance raises the cold threshold, while only slightly raising the hot threshold. Raising RTB lowers both the hot and cold thresholds, while lowering RTB raises both thresholds. Thermal Shutdown Thermal shutdown limits total power dissipation in the MAX8895_. When the junction temperature exceeds +160NC (typ), the device turns off, allowing the MAX8895_ to cool. The MAX8895_ turn on and begin soft-start after the junction temperature cools by 20NC (typ). This results in a pulsed charge current during continuous thermaloverload conditions. External Clock (MAX8895Y) The MAX8895Y includes full-speed USB 2.0 compatibility. USB 2.0 full speed requires that the system clock of the transceiver is within Q2500ppm, over temperature, aging, etc. Therefore, the MAX8895Y requires an external resonator or clock source to stay within this limit. The MAX8895Y local oscillator and internal digital clocks are derived from the reference clock at the XIN input. External Crystal/Ceramic Resonator (MAX8895Y) XIN and XOUT are used to interface to an external 12MHz crystal or ceramic resonator. Connect a 33pF load capacitor from both XIN/XOUT to ground. Requirements for the external resonator/crystal for MAX8895Y: Frequency: 12MHz Q0.25% CLOAD: 33pF Q20% Drive level: 200FW Series resonance resistance: 60I (maximum), 30I (typical) Maxim Integrated Note: Series resonance resistance is the resistance observed when the resonator is in the series resonant condition. This is a parameter often stated by quartz crystal vendors and is called R1. When a resonator is used in the parallel resonant mode with an external load capacitance, as is the case with the MAX8895Y oscillator circuit, the effective resistance is sometimes stated. The effective resistance at the loaded frequency of oscillation is: C O R EFF = R1x 1 + C LOAD 2 where: R1 = Series resonance resistance CO = Crystal capacitor CLOAD = External load capacitance For typical CO and CLOAD values, the effective resistance can be greater than R1 by a factor of 2. External Clock (MAX8895Y) The MAX8895Y can also be driven from an external clock. The MAX8895Y accepts an external clock input at XIN. The external clock can either be a digital level square wave or sinusoidal and this may be directly coupled to XIN without the need for additional components. If the peaks of the reference clock are above VINT_3V3 or below ground, the clock signal must be driven through a DC-blocking capacitor (approximately 33pF) connected to XIN. The external clock source can either be enabled using the UOK or INT_3V3 signals depending on if the clock source is active-low or active-high enabled. If the INT_3V3 rail is used, ensure that no significant load is taken from this output since this affects the performance of the MAX8895Y. Clock Timing Accuracy (MAX8895Y) USB 2.0 specification requires the system clock to be within Q2500ppm over temperature, aging, etc. It is recommended to use a clock source with tighter initial accuracy to ensure that over time the accuracy of Q2500ppm is still valid. ESD Protection D+, D-, and VBUS_ possess extra protection against static electricity to protect the devices up to Q8kV (HBM). The ESD structures withstand high ESD in all operating modes: normal operation, suspend mode, and powered down. VBUS_ requires 1FF ceramic capacitors connected to ground as close as possible to the pins. 41 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration ESD Test Conditions ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test setup, test methodology, and test results. Figure 26 shows the Human Body Model, and Figure 27 shows the current waveform generated when discharged into a low impedance. This model consists of a 100pF capacitor charged to the ESD voltage of interest, which then discharges into the test device through a 1.5kI resistor. Applications Information Capacitor Selection Ceramic X5R or X7R dielectric capacitors are recommended for best operation. When selecting ceramic capacitors in the smallest available case size for a given value, ensure that the capacitance does not degrade significantly with DC bias. Generally, ceramic capacitors with high values and very small case size have poor DC bias characteristics. Evaluate capacitors carefully before using. Ground Connections Minimize trace lengths between the bypass capacitors and ground. Use separate digital/power ground (DGND) RD 1.5kI CHARGE-CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE CS 100pF Recommended PCB Layout and Routing Place all bypass capacitors for INT_3V3, VBUS_, VBAT_, and VSYS_ as close as possible to the device. Connect the battery to BAT_A and BAT_B as close as possible to the device to provide accurate battery voltage sensing. Make all high-current traces short and wide to minimize voltage drops. When using the MAX8895Y, place the external crystal and load capacitors as close as possible to the MAX8895Y. The crystal and load capacitors should be kept as far away as possible from the D+/D- traces. Refer to the MAX8895 Evaluation Kit for an example layout. The MAX8895 Evaluation Kit supports the MAX8895V/MAX8895X and MAX8895Y. Ir IP 100% 90% DISCHARGE RESISTANCE STORAGE CAPACITOR and analog ground (AGND) copper areas, and connect them together at the negative terminal of the battery. The pins and/or external components for KB_TM, crystal load capacitors, ISET, IDN, CT, thermistor, and INT_3V3 should connect to a quiet analog ground. All other ground connections should connect to DGND. PEAK-TO-PEAK RINGING (NOT DRAWN TO SCALE) AMPERES DEVICE UNDER TEST 36.8% 10% 0 0 tRL TIME tDL CURRENT WAVEFORM Figure 26. Human Body Test Model 42 Figure 27. Human Body Model Current Waveform Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Typical Operating Circuit Chip Information PROCESS: BiCMOS VBUS_ BUS_ SYS_ Ordering Information SYSTEM LOAD D+ D- CONTROL LOGIC CHARGE AND SYSTEM LOAD SWITCH USB INTERFACE BAT_A/ BAT_B OSCILLATOR Maxim Integrated MAX8895V MAX8895W MAX8895X MAX8895Y USB INTERFACE PIN-PACKAGE TYPE 25 WLP MAX8895VEWA+T Low speed 2.36mm x 2.36mm 25 WLP MAX8895WEWA+T** Low speed 2.36mm x 2.36mm 25 WLP MAX8895XEWA+T Low speed 2.36mm x 2.36mm 25 WLP MAX8895YEWA+T Full speed 2.36mm x 2.36mm Note: All devices are specified over the -40C to +85C operating temperature range. +Denotes a lead(Pb)-free/RoHS-compliant package. T = Tape and reel. **Contact factory for availability. PART 1-CELL Li+ 43 MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 25 WLP W252D2+1 21-0453 Refer to Applications Note 1891 PIN 1 INDICATOR E MARKING COMMON DIMENSIONS 1 A A3 A 0.64 0.05 A1 0.19 0.03 0.45 REF A2 AAAA D A2 0.05 S S TOP VIEW 0.025 BASIC A3 A1 A See Note 7 SIDE VIEW E1 SE b 0.27 D1 1.60 E1 1.60 e 0.40 BASIC SD 0.00 BASIC SE 0.00 BASIC 0.03 e B E E SD D C D1 B A 1 2 3 4 5 A b 0.05 M S D DEPOPULATED BUMPS PKG. CODE MIN MAX MIN MAX W252D2+1 2.25 2.36 2.25 2.36 NONE W252F2+1 2.02 2.16 2.02 2.16 NONE W252G2+1 2.32 2.44 2.22 2.34 NONE W252H2+1 2.41 2.44 2.41 2.44 NONE AB BOTTOM VIEW NOTES: 1. Terminal pitch is defined by terminal center to center value. 2. Outer dimension is defined by center lines between scribe lines. 3. All dimensions in millimeter. 4. Marking shown is for package orientation reference only. 5. Tolerance is 0.02 unless specified otherwise. 6. All dimensions apply to PbFree (+) package codes only. 7. Front - side finish can be either Black or Clear. - DRAWING NOT TO SCALE - 44 TITLE APPROVAL PACKAGE OUTLINE 25 BUMPS, WLP PKG. 0.4mm PITCH DOCUMENT CONTROL NO. 21-0453 REV. D 1 1 Maxim Integrated MAX8895V/MAX8895W/MAX8895X/MAX8895Y Li-Ion Chargers with Smart Power Selector, Adapter Type Detection, and USB Enumeration Revision History REVISION NUMBER REVISION DATE DESCRIPTION 0 7/10 Initial release 1 10/10 Added MAX8895W to data sheet 2 2/11 Added patent information 3 4/11 Added contact factory note for MAX8895W 4 9/12 Added MAX8895V to data sheet PAGES CHANGED -- 1-38 1 1 1-42 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. 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