bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 2.5A, Dual-Input, Single Cell Switchmode Li-Ion Battery Charger with Power Path Management and I2C Interface Check for Samples: bq24160, bq24161, bq24163, bq24168 FEATURES APPLICATIONS * * * * * 1 2 * * * * * * * * * * High-Efficiency Switch Mode Charger with Separate Power Path Control - Make a GSM Call with a Deeply Discharged Battery or No Battery - Instantly Start Up System from a Deeply Discharged Battery or No Battery Dual Input Charger Highly Integrated Battery N-Channel MOSFET Controller for Power Path Management - 20 V input rating, with Overvoltage Protection (OVP) - 6.5 V for USB Input - 10.5 V for IN input (bq24160/1/3) - 6.5 V for IN input (bq24168) - Integrated FETs for Up to 2.5A Charge Rate - Up to 2.5 A from IN Input (input current limit) - Up to 1.5 A from USB Input (input current limit) Safe and Accurate Battery Management Functions - 0.5% Battery Regulation Accuracy - 10% Charge Current Accuracy Charge Parameters Programmed Using I2CTM Interface - Charge Voltage, Current, Termination Threshold, Input Current Limit, VINDPM Threshold Voltage Based, NTC Monitoring Input - JEITA Compatible (bq24160/3/8) Thermal Regulation Protection for Output Current Control Low Battery Leakage Current, BAT ShortCircuit Protection Soft-Start Feature to Reduce Inrush Current Thermal Shutdown and Protection Available in small 2.8mm x 2.8mm 49-ball WCSP or 4mm x 4mm QFN-24 Packages Handheld Products Portable Media Players Portable Equipment Netbook and Portable Internet Devices DESCRIPTION The bq24160/ bq24161/ bq24163/ bq24168 are highly integrated single cell Li-Ion battery charger and system power path management devices targeted for space-limited, portable applications with high capacity batteries. The single cell charger has dual inputs which allow operation from either a USB port or higher-power input supply (i.e., AC adapter or wireless charging input) for a versatile solution. The two inputs are fully isolated from each other and are easily selectable using the I2C interface. APPLICATION SCHEMATIC AC Adapter or Wireless Power SW IN System Load PMIDI USB VBUS D+ D- GND BOOT SYS PMIDU D+ D- BAT SDA SCL HOST INT TS PGND TEMP PACK+ DRV + - VSYS PACK- 1 2 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. I2C is a trademark of NXP Semiconductor. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright (c) 2011-2012, Texas Instruments Incorporated bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. DESCRIPTION (CONTINUED) The power path management feature allows the bq2416x to power the system from a high-efficiency DC-to-DC converter while simultaneously and independently charging the battery. The charger monitors the battery current at all times and reduces the charge current when the system load requires current above the input current limit. This allows for proper charge termination and timer operation. Under normal battery charging conditions, the system voltage is approximately equal to the battery voltage, however if the battery is deeply discharged, the system voltage does not drop below 3.5V. This minimum system voltage support enables the system to run with a defective or absent battery pack and enables instant system turn-on even with a totally discharged battery or no battery. The power-path management architecture also permits the battery to supplement the system current requirements when the adapter cannot deliver the peak system currents. This enables the use of a smaller adapter. The 2.5A input current capability allows for GSM phone calls as soon as the adapter is plugged in regardless of the battery voltage. The charge parameters are programmable using the I2C interface. The battery is charged in three phases: precharge, fast-charge constant current and constant voltage. In all charge phases, an internal control loop monitors the IC junction temperature and reduces the charge current if the internal temperature threshold is exceeded. Additionally, a voltage-based battery pack thermistor monitoring input (TS) is included that monitors battery temperature for safe charging. The TS function for bq24160, bq24163 and bq24168 is JEITA compatible. 2 Copyright (c) 2011-2012, Texas Instruments Incorporated bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 ORDERING INFORMATION PART NUMBER USB OVP IN OVP USB DETECTION TIMERS (Safety and Watchdog) NTC MONITORING VBATSHRT/ IBATSHRT VMINSYS PKG bq24160YFFR 6.5V 10.5V D+/D- Yes JEITA 3.0V 50mA 3.5V WCSP bq24160YFFT 6.5V 10.5V D+/D- Yes JEITA 3.0V 50mA 3.5V WCSP bq24160RGER 6.5V 10.5V D+/D- Yes JEITA 3.0V 50mA 3.5V QFN bq24160RGET 6.5V 10.5V D+/D- Yes JEITA 3.0V 50mA 3.5V QFN bq24161YFFR 6.5V 10.5V PSEL Yes Standard 2.0V 50mA 3.5V WCSP bq24161YFFT 6.5V 10.5V PSEL Yes Standard 2.0V 50mA 3.5V WCSP bq24161RGER 6.5V 10.5V PSEL Yes Standard 2.0V 50mA 3.5V QFN bq24161RGET 6.5V 10.5V PSEL Yes Standard 2.0V 50mA 3.5V QFN bq24163RGER 6.5V 10.5V D+/D- Yes JEITA 2.0V 50mA 3.2V WCSP bq24163YFFT 6.5V 10.5V D+/D- Yes JEITA 2.0V 50mA 3.2V WCSP bq24163YFFR 6.5V 10.5V D+/D- Yes JEITA 2.0V 50mA 3.2V QFN bq24163RGET 6.5V 10.5V D+/D- Yes JEITA 2.0V 50mA 3.2V QFN bq24168YFFR 6.5V 6.5V PSEL No JEITA 2.0V 50mA 3.5V WCSP bq24168YFFT 6.5V 6.5V PSEL No JEITA 2.0V 50mA 3.5V WCSP Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 3 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com ABSOLUTE MAXIMUM RATINGS over operating free-air temperature range (unless otherwise noted) (1) VALUE IN, USB Pin voltage range (with respect to VSS) Input current (Continuous) Output sink current MAX UNITS -2 20 V PMIDI, PMIDU, BOOT -0.3 20 V SW -0.7 12 V SDA, SCL, SYS, BAT, STAT, BGATE, DRV, TS, D+, D-, INT, PSEL, CD -0.3 7 V -0.3 7 V BOOT to SW Output current (Continuous) MIN SW 4.5 A SYS, BAT 3.5 A IN 2.75 A USB 1.75 A STAT 10 mA INT 1 mA Operating free-air temperature range -40 85 C Junction temperature, TJ -40 125 C Storage temperature, TSTG -65 150 C Lead temperature (soldering, 10 s) 300 (1) C 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 under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. All voltage values are with respect to the network ground terminal unless otherwise noted. THERMAL INFORMATION THERMAL METRIC (1) bq2416x 49 PINS (YFF) 24 PINS (RGE) JA Junction-to-ambient thermal resistance 49.8 32.6 JCtop Junction-to-case (top) thermal resistance 0.2 30.5 JB Junction-to-board thermal resistance 1.1 3.3 JT Junction-to-top characterization parameter 1.1 0.4 JB Junction-to-board characterization parameter 6.6 9.3 JCbot Junction-to-case (bottom) thermal resistance n/a 2.6 (1) UNITS C/W For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953. RECOMMENDED OPERATING CONDITIONS over operating free-air temperature range (unless otherwise noted) VIN VUSB MIN MAX IN voltage range 4.2 18 IN operating voltage range (bq24160/1/3) 4.2 10 IN operating voltage range (bq24168) 4.2 6 USB voltage range 4.2 18 USB operating range 4.2 6 UNITS V V IIN Input current, IN input 2.5 A IUSB Input current USB input 1.5 A ISYS Ouput Current from SW, DC 3 A Charging 2.5 A Discharging, using internal battery FET 2.5 A 125 C IBAT TJ 4 Operating junction temperature range Submit Documentation Feedback 0 Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 ELECTRICAL CHARACTERISTICS Circuit of , VSUPPLY = VUSB or VIN (whichever is supplying the IC), VUVLO < VSUPPLY < VOVP and VSUPPLY > VBAT+VSLP, TJ = -40C - 125C and TJ = 25C for typical values (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT INPUT CURRENTS VUVLO < VSUPPLY < VOVP and VSUPPLY > VBAT+VSLP PWM switching ISUPPLY Supply current for control (VIN or VUSB) IBATLEAK Leakage current from BAT to the Supply 0C < TJ < 85C, VBAT = 4.2V, VUSB = VIN = 0V IBAT_HIZ Battery discharge current in High Impedance mode, (BAT, SW, SYS) 0C< TJ < 85C, VBAT = 4.2V, VSUPPLY = 5V or 0V, SCL, SDA = 0 V or 1.8V, High-Z Mode 15 PWM NOT switching mA 5 0C < TJ < 85C, High-Z Mode 175 A 5 A 55 A POWER-PATH MANAGEMENT bq24160/1/8 VBAT < VMINSYS VSYS(REG) System regulation voltage 3.60 3.7 3.3 3.4 3.5 VBATREG + 1.5% VBATREG + 3.0% VBATREG + 4.17% bq24160/1/8 3.4 3.5 3.62 V bq24163 3.1 3.2 3.3 V bq24163 Battery FET turned off VMINSYS VBAT < VMINSYS, Input current limit or VINDPM active Minimum system regulation voltage 3.82 V VBSUP1 Enter supplement mode threshold VBAT > 2.5V VBAT -30mV VBSUP2 Exit supplement mode threshold VBAT > 2.5V VBAT -10mV V ILIM(discharge) Current limit, discharge or supplement mode Current monitored in internal FET only. 7 A tDGL(SC1) Deglitch time, SYS short circuit during discharge or supplement mode Measured from (VBAT - VSYS) = 300mV to BAT highimpedance 250 s tREC(SC1) Recovery time, SYS short circuit during discharge or supplement mode 60 ms Battery range for BGATE and supplement mode operation 2.5 4.5 V V BATTERY CHARGER RON(BAT-SYS) Internal battery charger MOSFET on-resistance Charge Voltage VBATREG Measured from BAT to SYS, VBAT = 4.2V YFF pkg 37 57 RGE pkg 50 70 m Operating in voltage regulation, Programmable range Voltage regulation accuracy Fast charge current range VBATSHRT VBAT < VBAT(REG) programmable range Fast charge current accuracy 0C to 125C VBATSHRT Battery short circuit threshold 100mV Hysteresis IBATSHRT Battery short circuit current tDGL(BATSHRT) Deglitch time for battery short circuit to fastcharge transition ITERM Termination charge current accuracy tDGL(TERM) Deglitch time for charge termination Both rising and falling, 2mV overdrive, tRISE, tFALL = 100ns VRCH Recharge threshold voltage Below VBATREG tDGL(RCH) Deglitch time VDETECT Battery detection threshold ICHARGE 3.5 4.44 -1% 1% 550 2500 -10% +10% bq24161/3/8 1.9 2.0 2.1 bq24160 2.9 3.0 3.1 mA V VBAT < VBATSHRT ITERM = 50mA -35% ITERM 100mA -15% 50 mA 32 ms +35% +15% 32 ms 120 mV VBAT falling below VRCH, tFALL=100ns 32 ms During battery detection source cycle 3.3 V During battery detection sink cycle 3.0 2.5 mA 250 ms IDETECT Battery detection current before charge done (sink current) Termination enabled (EN_TERM = 1) tDETECT Battery detection time Termination enabled (EN_TERM = 1) VIH(CD) CD Input high logic level VIL(CD) CD Input low logic level 1.3 V 0.4 Copyright (c) 2011-2012, Texas Instruments Incorporated V Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 V 5 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com ELECTRICAL CHARACTERISTICS (Continued) Circuit of Figure 23, VSUPPLY = VUSB or VIN (whichever is supplying the IC), VUVLO < VSUPPLY < VOVP and VSUPPLY > VBAT+VSLP, TJ = -40C - 125C and TJ = 25C for typical values (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT INPUT CURRENT LIMITING IIN_USB Input current limit threshold (USB input) USB charge mode, VUSB = 5V, DC Current pulled from SW IUSBLIM = USB100 90 95 100 IUSBLIM = USB500 450 475 500 IUSBLIM = USB150 135 142.5 150 IUSBLIM = USB900 800 850 900 mA IUSBLIM = USB800 IIN_IN Input current limit threshold (IN input) VIN_DPM Input based DPM threshold range 700 750 800 IUSBLIM = 1.5A 1250 1400 1500 IINLIM = 1.5A 1.35 1.5 1.65 IINLIM = 2.5A 2.3 2.5 2.8 Charge mode, programmable via I2C, both inputs 4.2 4.76 -2 +2% IN charge mode, VIN = 5V, DC Current pulled from SW VIN_DPM threshold accuracy A V VDRV BIAS REGULATOR VDRV Internal bias regulator voltage IDRV DRV output current VSUPPLY > 5.45V VDO_DRV DRV Dropout voltage (VSUPPLY - VDRV) 5 5.2 5.45 10 V mA ISUPPLY = 1A, VSUPPLY = 5V, IDRV = 10mA 450 mV 0.4 V 1 A STATUS OUTPUT (STAT, INT) VOL Low-level output saturation voltage IO = 10mA, sink current IIH High-level leakage current VSTAT = VINT = 5V VUVLO IC active threshold voltage VIN rising 3.6 3.8 VUVLO_HYS IC active hysteresis VIN falling from above VUVLO 120 150 VSLP Sleep-mode entry threshold, VSUPPLY-VBAT 2.0V VBAT VBATREG, VIN falling VSLP_EXIT Sleep-mode exit hysteresis 2.0V VBAT VBATREG Deglitch time for supply rising above VSLP+VSLP_EXIT Rising voltage, 2mV over drive, tRISE = 100ns PROTECTION VBAD_SOURCE 0 40 100 mV 100 175 mV 30 Bad source detection threshold VBOVP Input supply OVP threshold voltage IN, VIN Rising (bq24160/1/3) VOVP hysteresis ms 6.3 6.5 6.7 10.3 10.5 10.7 6.3 6.5 6.7 1.025 x VBATREG 1.05 x VBATREG Supply falling from VOVP 100 Battery OVP threshold voltage VBAT threshold over VOREG to turn off charger during charge VBOVP hysteresis Lower limit for VBAT falling from above VBOVP VBATUVLO Battery undervoltage lockout threshold VBAT rising, 100mV hysteresis ILIMIT Cycle-by-cycle current limit VSYS shorted TSHTDWN Thermal trip 4.9 V % of VBATREG 2.5 4.1 V mV 1.075 x VBATREG 1 V 5.6 165 Thermal hysteresis TREG V 32 IN, VIN Rising (bq24168) VOVP(HYS) ms VIN_DPM - 80 mV USB, VUSB Rising V mV 40 Deglitch on bad source detection VOVP 4 A C 10 Thermal regulation threshold Charge current begins to cut off Safety timer accuracy (bq24160/1/3 Only) 120 -20% C 20% PWM Internal top reverse blocking MOSFET on-resistance 95 175 IIN_LIMIT = 500mA, Measured from IN to PMIDI 45 80 m Internal top N-channel Switching MOSFET onresistance Measured from PMIDU to SW 100 175 Measured from PMIDI to SW 65 110 Internal bottom N-channel MOSFET on-resistance Measured from SW to PGND fOSC Oscillator frequency DMAX Maximum duty cycle DMIN Minimum duty cycle 6 IIN_LIMIT = 500mA, Measured from USB to PMIDU m 1.35 65 115 m 1.50 1.65 MHz 95% 0% Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 ELECTRICAL CHARACTERISTICS (Continued) Circuit of , VSUPPLY = VUSB or VIN (whichever is supplying the IC), VUVLO < VSUPPLY < VOVP and VSUPPLY > VBAT+VSLP, TJ = -40C - 125C and TJ = 25C for typical values (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX 29.7 30 30.5 UNIT BATTERY-PACK NTC MONITOR VHOT High temperature threshold VTS falling VHYS(HOT) Hysteresis on high threshold VTS rising VWARM High temperature threshold VTS falling VHYS(WARM) Hysteresis on high threshold VTS rising VCOOL Low temperature threshold VTS falling VHYS(COOL) Hysteresis on low threshold VTS rising VCOLD Low temperature threshold VTS falling VHYS(COLD) Hysteresis on low threshold VTS rising TSOFF TS Disable threshold VTS rising, 2%VDRV hysteresis tDGL(TS) Deglitch time on TS change %VDRV 1 37.9 38.3 39.6 %VDRV 1 56 56.5 56.9 %VDRV 1 59.5 60 60.4 %VDRV 1 70 73 50 %VDRV ms D+/D- DETECTION (bq24160) VD+_SRC D+ Voltage Source ID+_SRC D+ Connection Check Current Source 0.5 ID-_SINK D- Current Sink ID_LKG Leakage Current into D+/D- 0.6 7 50 100 0.7 V 14 A 150 A D-, switch open -1 1 A D+, switch open -1 1 A VD+_LOW D+ Low Comparator Threshold 0.8 VD-_LOWdatref D- Low Comparator Threshold 250 400 mV V RD-_DWN D- Pulldown for Connection Check 14.25 24.8 k BATGD OPERATION VBATGD Good Battery threshold 3.6 Deglitch for good battery threshold VBAT rising to HIGH-Z mode, DEFAULT Mode Only 3.8 3.9 32 V ms I2C COMPATIBLE INTERFACE VIH Input low threshold level VPULL-UP = 1.8V, SDA and SCL VIL Input low threshold level VPULL-UP = 1.8V, SDA and SCL 0.4 VOL Output low threshold level IL = 10mA, sink current 0.4 IBIAS High-Level leakage current VPULL-UP = 1.8V, SDA and SCL tWATCHDOG Watchdog timer timeout (bq24160/1/3 Only) Copyright (c) 2011-2012, Texas Instruments Incorporated 1.3 V 1 30 Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 V V A s 7 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com BLOCK DIAGRAM PMIDU PMIDI 5.2-V Reference DRV IN Q1 USB 5A + BOOT CbC Current Limit IN IINLIM USB IUSBLIM IN VINDPM DC-DC CONVERTER PWM LOGIC, COMPENSATION AND BATTERY FET CONTROL USB VINDPM VSYS(REG) Q2 IBAT(REG) SW VBAT(REG) DIE Temp Regulation Q3 PGND VSUPPLY IBAT Termination Comparator + VINOVP Enable Linear Charge Sleep Comparators + Hi-Z Mode 2 Supplement Comparator I C Interface + VBAT bq24160/3 1.5A/USB100 DISABLE TS COLD bq24161/8 1C/0.5C PSEL bq24160/2/3 TS COOL VBATREG - 0.14V STAT TS WARM + D- USB Adapter Detection Circuitry VDRV VBOVP Comparator VBAT VBATOVP + D+ VSYS VBSUP + SCL BGATE + SDA Hi-Z Mode + CD VBAT VBATGD VBATSC Comparator VBAT Enable IBATSHRT VBATSHRT Good Battery Circuit + VIN VBAT + VSLP VSYSREG Comparator VSYS VMINSYS + + BAT Recharge Comparator VBATREG - 0.12V VBAT + VUSB VBAT + VSLP Start Recharge Cycle Q4 + OVP Comparators VIN SYS + VUSBOVP References SUPPLY_SEL Termination Reference + VUSB + DISABLE TS HOT INT 8 CHARGE CONTROLLER with Timers (160/1/3) Submit Documentation Feedback TS Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 19 20 21 23 22 24 19 20 22 21 23 PMIDI BOOT IN USB CD PMIDU PMIDI BOOT IN USB CD PMIDU 24 PIN CONFIGURATION D- 1 18 SW N.C. 1 18 SW D+ 2 17 PGND PSEL 2 17 PGND SCL 3 16 SGND SCL 3 SDA 4 15 PGND SDA 4 PGND 5 14 SYS GND 5 14 SYS DRV 6 13 SYS DRV 6 13 SYS bq24160 bq24163 16 SGND bq24161 bq24168 15 PGND 12 BAT TS 11 BAT 10 BGATE 8 STAT 9 7 /BATGD 11 BAT 12 BAT TS 10 BGATE 8 STAT 9 7 INT Figure 1. 24-Pin QFN (RGE) bq24160/3 (Top View) 1 2 3 4 A IN IN IN IN B PMIDI PMIDI PMIDI C SW SW D PGND E bq24161/8 (Top View) 5 6 7 IN USB USB USB PMIDI PMIDI PMIDU PMIDU PMIDU SW SW SW SW SW SW PGND PGND PGND PGND PGND PGND PGND PGND PSEL N.C. CD SDA SCL BOOT SYS SYS SYS SYS BGATE INT DRV BAT BAT BAT BAT TS STAT PGND 2 3 7 USB USB USB A IN IN IN PMIDI PMIDU PMIDU PMIDU B PMIDI PMIDI SW SW SW SW SW C SW PGND PGND PGND PGND PGND PGND D PGND D+ D- CD SDA SCL BOOT E SYS SYS SYS SYS BGATE INT DRV F G 5 1 6 4 F BAT BAT BAT BAT TS STAT PGND G Figure 2. 49-Ball 2.8mm x 2.8mm WCSP (YFF) Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 9 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com PIN FUNCTIONS PIN NAME PIN NO. bq24160/3 PIN NO. bq24161/8 I/O DESCRIPTION YFF RGE YFF RGE G1-G4 11, 12 G1-G4 11, 12 BGATE F5 10 F5 10 O External Discharge MOSFET Gate Connection - BGATE drives an external PChannel MOSFET to provide a very low-resistance discharge path. Connect BGATE to the gate of the external MOSFET. BGATE is low during high impedance mode and when no input is connected. BOOT E7 19 E7 19 I High Side MOSFET Gate Driver Supply - Connect a 0.01F ceramic capacitor (voltage rating > 10V) from BOOT to SW to supply the gate drive for the high side MOSFETs. CD E4 24 E4 24 I IC Hardware Disable Input - Drive CD high to place the bq2416x in high-z mode. Drive CD low for normal operation. Do not leave CD unconnected. D+ E2 2 -- -- I D- E3 1 -- -- I D+ and D- Connections for USB Input Adapter Detection - When a charge cycle is initiated by the USB input, and a short is detected between D+ and D-, the USB input current limit is set to 1.5A. If a short is not detected, the USB100 mode is selected. The D+/D- detection has no effect on the IN input. DRV F7 6 F7 6 O Gate Drive Supply - DRV is the bias supply for the gate drive of the internal MOSFETs. Bypass DRV to PGND with a 1F ceramic capacitor. DRV may be used to drive external loads up to 10mA. DRV is active whenever the input is connected and VSUPPLY > VUVLO and VSUPPLY > (VBAT + VSLP) A1- A4 21 A1- A4 21 I Input power supply - IN is connected to the external DC supply (AC adapter or alternate power source). Bypass IN to PGND with at least a 1F ceramic capacitor. F6 7 F6 7 O Status Output - INT is an open-drain output that signals charging status and fault interrupts. INT pulls low during charging. INT is high impedance when charging is complete or the charger is disabled. When a fault occurs, a 128s pulse is sent out as an interrupt for the host. INT is enabled/disabled using the EN_STAT bit in the control register. Connect INT to a logic rail through a 100k resistor to communicate with the host processor. PGND D1-D7, E1, G7 5, 15, 16, 17 D1-D7, E1, G7 5, 15, 16, 17 -- Ground terminal - Connect to the thermal pad (for QFN only) and the ground plane of the circuit. PMIDI B1-B4 20 B1-B4 20 O Reverse Blocking MOSFET and High Side MOSFET Connection Point for High Power Input - Bypass PMIDI to GND with at least a 4.7F ceramic capacitor. Use caution when connecting an external load to PMIDI. The PMIDI output is not current limited. Any short on PMIDI will damage the IC. PMIDU B5-B7 23 B5-B7 23 O Reverse Blocking MOSFET and High Side MOSFET Connection Point for USB Input - Bypass PMIDU to GND with at least a 4.7F ceramic capacitor. Use caution when connecting an external load to PMIDU. The PMIDU output is not current limited. Any short on PMIDU will damage the IC. PSEL -- -- E2 2 SCL E6 3 E6 3 SDA E5 4 E5 4 I/O I2C Interface Data - Connect SDA to the logic rail through a 10k resistor. STAT G6 8 G6 8 O Status Output - STAT is an open-drain output that signals charging status and fault interrupts. STAT pulls low during charging. STAT is high impedance when charging is complete or the charger is disabled. When a fault occurs, a 128s pulse is sent out as an interrupt for the host. STAT is enabled /disabled using the EN_STAT bit in the control register. Pull STAT up to a logic rail thruogh an LED for visual indication or through a 10k resistor to communicate with the host processor. SW C1-C7 18 C1-C7 18 O Inductor Connection - Connect to the switched side of the external inductor. SYS F1-F4 13, 14 F1-F4 13,14 I System Voltage Sense and Charger FET Connection - Connect SYS to the system output at the output bulk capacitors. Bypass SYS locally with at least 10F. A 47F bypass capacitor is recommended for optimal transient response. BAT IN INT 10 Submit Documentation Feedback I/O Battery Connection - Connect to the positive terminal of the battery. Additionally, bypass BAT to GND with at least a 1F capacitor. USB Source Detection Input - Drive PSEL high to indicate that a USB source is connected to the USB input. When PSEL is high, the IC starts up with a 100mA input current limit for USB. Drive PSEL low to indicate that an AC Adapter is connected to the USB input. When PSEL is low, the IC starts up with a 1.5A input current limit for USB. PSEL has no effect on the IN input. Do not leave PSEL unconnected. I I2C Interface Clock - Connect SCL to the logic rail through a 10k resistor. Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 PIN FUNCTIONS (continued) PIN NAME TS USB Thermal Pad PIN NO. bq24160/3 PIN NO. bq24161/8 I/O DESCRIPTION 9 I Battery Pack NTC Monitor - Connect TS to the center tap of a resistor divider from DRV to GND. The NTC is connected from TS to GND. The TS function provides 4 thresholds for JEITA compatibility (160/163/168 only). TS faults are reported by the I2C interface. See the NTC Monitor section for more details on operation and selecting the resistor values. Connect TS to DRV to disable the TS function. A5-A7 22 I USB Input Power Supply - USB is connected to the external DC supply (AC adapter or USB port). Bypass USB to PGND with at least a 1F ceramic capacitor. -- Pad -- There is an internal electrical connection between the exposed thermal pad and the PGND pin of the device. The thermal pad must be connected to the same potential as the PGND pin on the printed circuit board. Do not use the thermal pad as the primary ground input for the device. PGND pin must be connected to ground at all times. YFF RGE YFF RGE G5 9 G5 A5-A7 22 -- Pad TYPICAL APPLICATION CIRCUIT ADAPTER 1.5 mH IN SW PMIDI 1 mF VBUS D+ DGND BOOT USB SYS 10 mF PMIDU 1 mF System Load 0.01 mF 4.7 mF PGND 4.7 mF BGATE DRV BAT 1 mF VDRV 1 mF STAT GSM PA PACK+ TS TEMP VSYS (1.8V) D+ DPACK- HOST bq24160 INT SDA GPIO1 SCL SCL SDA Figure 3. bq24160, Shown with no External Discharge FET, PA Connected to Battery Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 11 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com ADAPTER 1.5 mH IN SW PMIDI 1 mF System Load 0.01 mF 4.7 mF BOOT VBUS D+ DGND USB SYS 10 mF PMIDU 1 mF PGND 4.7 mF BGATE DRV GSM PA BAT 1 mF VDRV 1 mF STAT PACK+ TS TEMP VSYS (1.8V) PSEL USB PHY PACK- HOST bq24161 INT SDA GPIO1 SCL SCL SDA Figure 4. - bq24161, Shown with External Discharge FET, PA Connected to System for GSM Call Support with a Deeply Discharged or No Battery TYPICAL CHARACTERISTICS USB Plug-In with Battery Connected Conditions: USB500, 925mA Charge Setting Figure 5. Adapter Detection USB IN Plug-in with Battery Connected Conditions: 1500mA ILIM, 1300mA Charge Setting Figure 6. Battery Insert During Battery Detection Conditions: Termination Enabled 12 Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 TYPICAL CHARACTERISTICS (continued) Figure 7. Figure 8. Battery Pull During Charging Load Transient into DPPM Conditions: Termination Enabled Conditions: MINSYS Operation, USB1500, 200mA-1400mA Load Step on SYS Figure 10. Figure 9. OVP Fault USB Input Load Transient into Supplement Mode VUSB 5 V/div VSYS 5 V/div VBAT VSTAT/INT 1 V/div 5 V/div VSW IUSB 500 mA/div 1 A/div IBAT 500 mA/div IBAT 10 ms/div 4 ms/div Conditions: MINSYS Operation, USB500, 200mA - 1400mA Load Step on SYS Figure 11. Figure 12. USB Efficiency 100 90 90 80 80 70 70 Efficiency (%) Efficiency (%) IN Efficiency 100 60 50 40 30 60 50 40 30 VIN = 5 V VIN = 7 V VIN = 9 V 20 10 0 0.1 1 System Current (A) 20 3 0 0.1 1 System Current (A) G001 Conditions: Charge Disabled, SYS loaded, VBATREG = 3.6V, IN2500 ILIM Figure 13. Copyright (c) 2011-2012, Texas Instruments Incorporated VUSB = 5 V VUSB = 6 V 10 2 G002 Conditions: Charge Disabled, SYS loaded, VBATREG = 3.6V, USB1500 ILIM Figure 14. Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 13 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com TYPICAL CHARACTERISTICS (continued) Battery Regulation vs Temperature 3.85 4.21 SYSREG Regulation MINSYS Regulation 4.208 3.8 4.206 Battery Regulation (V) SYSREG and MINSYS Regulation (V) SYSREG and MINSYS Regulation vs. Temperature 3.9 3.75 3.7 3.65 3.6 3.55 4.204 4.202 4.2 4.198 4.196 3.5 4.194 3.45 4.192 3.4 -50 0 50 Temperature (C) 100 4.19 150 0 Conditions: VBAT = 3V USB Input Current Limit vs. Temperature 400 300 200 100 6.5 6.4 6.3 6.2 6.1 0 50 Temperature (C) 100 6 -50 150 0 G005 50 Temperature (C) 100 150 G006 Conditions: USB input and IN input (bq24168) Figure 18. 10.5V OVP Threshold vs. Temperature Charge Current vs. Battery Voltage 10.7 2.1 Falling Edge Rising Edge 2.09 2.08 Charge Current (A) 10.5 V OVP Threshold (V) G004 Falling Edge Rising Edge 6.6 6.5 V OVP Threshold (V) USB Input Current Limit (mA) USB100 Current Limit USB500 Current Limit Conditions: USB100 and USB500 current limit, VUSB = 5V, VBAT = 3.6V Figure 17. 10.5 10.4 10.3 10.2 2.07 2.06 2.05 2.04 2.03 2.02 10.1 10 -50 2.01 0 50 Temperature (C) Figure 19. 14 125 6.7 500 10.6 100 6.5V OVP Threshold vs. Temperature 700 0 -50 50 75 Temperature (C) Conditions: VBATREG = 4.2V, No load, Termination Disabled Figure 16. Figure 15. 600 25 G003 Submit Documentation Feedback 100 150 2 2 2.5 G007 3 3.5 Battery Voltage (V) 4 4.5 G008 Conditions: ICHARGE = 2A, VIN = 5V, VBATREG = 4.44V Figure 20. Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 TYPICAL CHARACTERISTICS (continued) IBATSHRT vs. Battery Voltage 0.055 IBATSHRT (A) 0.054 0.053 0.052 0.051 0.05 0 0.5 1 1.5 2 Battery Voltage (V) 2.5 3 G009 Figure 21. DETAILED DESCRIPTION The bq24160/bq24161/bq24163/bq24168 are highly integrated single cell Li-Ion battery chargers and system power path management devices targeted for space-limited, portable applications with high capacity batteries. The dual-input, single-cell charger operates from either a USB port or alternate power source (i.e. wall adapter or wireless power input) for a versatile solution. The power path management feature allows the bq2416x to power the system from a high efficiency DC-to-DC converter while simultaneously and independently charging the battery. The charger monitors the battery current at all times and reduces the charge current when the system load requires current above the input current limit. This allows proper charge termination and enables the system to run with a defective or absent battery pack. Additionally, this enables instant system turn-on even with a totally discharged battery or no battery. The powerpath management architecture also permits the battery to supplement the system current requirements when the adapter cannot deliver the peak system currents. This enables the use of a smaller adapter. The 2.5 A current capability allows for GSM phone calls as soon as the adapter is plugged in regardless of the battery voltage. The charge parameters are programmable using the I2C interface. Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 15 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com CHARGE MODE OPERATION Charge Profile The internal battery MOSFET is used to charge the battery. When the battery is above the MINSYS votlage, the the internal FET is on to maximize efficiency and the PWM converter regulates the charge current into the battery. When battery is less than MINSYS, the SYS is regulated to VSYS(REG) and battery is charged using the battery FET to regulate the charge current. There are 5 loops that influence the charge current: * Constant current loop (CC) * Constant voltage loop (CV) * Thermal-regulation loop * Minimum system-voltage loop (MINSYS) * Input-voltage dynamic power-management loop (VIN-DPM) During the charging process, all five loops are enabled and the one that is dominant takes control. The bq2416x supports a precision Li-Ion or Li-Polymer charging system for single-cell applications. The Dynamic Power Path Management (DPPM) feature regulates the system voltage to a minimum of VMINSYS, so that startup is enabled even for a missing or deeply discharged battery. Figure 22 shows a typical charge profile including the minimum system output voltage feature. Precharge Phase Current Regulation Phase Voltage Regulation Phase Regulation voltage Charge Current Regulation Threshold System Voltage VSYS V BATSHORT Battery Voltage Charge Current Termination Current Threshold I BATSHORT 50mA Precharge to Close Pack Protector Linear Charge to Maintain Minimum System Voltage Battery FET is OFF Battery FET is ON Figure 22. Typical bq2416x Charging Profile PWM Controller in Charge Mode The bq2416x provides an integrated, fixed-frequency 1.5MHz voltage-mode controller to power the system and supply the charge current. The voltage loop is internally compensated and provides enough phase margin for stable operation, allowing the use of small ceramic capacitors with very low ESR. The input scheme for the bq2416x prevents battery discharge when the supply voltages are lower than VBAT and also isolates the two inputs from each other. The high-side N-MOSFET (Q1/Q2) switches to control the power delivered to the output. The DRV LDO provides a supply for the gate drive for the low side MOSFET, while a bootstrap circuit (BST) with an external bootstrap capacitor is used to boost up the gate drive voltage for Q1 and Q2. 16 Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 Both inputs are protected by a cycle-by-cycle current limit that is sensed through the high-side MOSFETs for Q1 and Q2. The threshold for the current limit is set to a nominal 5A peak current. The inputs also utilize an input current limit that limits the current from the power source. Battery Charging Process When the battery is deeply discharged or shorted (VBAT < VBATSHRT), the bq2416x applies IBATSHRT to close the pack protector switch and bring the battery voltage up to acceptable charging levels. During this time, the battery FET is linearly regulated and the system output is regulated to VSYS(REG). Once the battery rises above VBATSHRT, the charge current is regulated to the value set in the I2C register. The battery FET is linearly regulated to maintain the system voltage at VSYS(REG). Under normal conditions, the time spent in this region is a very short percentage of the total charging time, so the linear regulation of the charge current does not affect the overall charging efficiency for very long. If the die temperature does rise, the thermal regulation circuit reduces the charge current to maintain a die temperature less than 120C. If the current limit for the SYS output is reached (limited by the input current limit, or VIN_DPM), the SYS output drops to the VMINSYS output voltage. When this happens, the charge current is reduced to provide the system with all the current that is needed while maintaining the minimum system voltage. If the charge current is reduced to 0mA, pulling further current from SYS causes the output to fall to the battery voltage and enter supplement mode. (See the Dynamic Power Path Management section for more details.) Once the battery is charged enough so that the system voltage begins to rise above VSYS(REG), the battery FET is turned on fully and the battery is charged with the full programmed charge current set by the I2C interface, ICHARGE. The slew rate for the fast-charge current is controlled to minimize current and voltage overshoot during transients. The charge current is regulated to ICHARGE until the battery is charged to the regulation voltage. Once the battery voltage is close to the regulation voltage, VBATREG, the charge current is tapered down as shown in Figure 22 while the SYS output remains connected to the battery. The voltage-regulation feedback occurs by monitoring the battery-pack voltage between the BAT and PGND pins. The bq2416x is a fixed single-cell voltage version, with adjustable regulation voltage (3.5V to 4.44V), programmed using the I2C interface. The bq2416x monitors the charging current during the voltage-regulation phase. Once the termination threshold, ITERM, is detected and the battery voltage is above the recharge threshold, the bq2416x terminates charge and turns off the battery charging FET. The system output is regulated to the VSYS(REG) and supports the full current available from the input and the battery supplement mode is available. (See the Dynamic Power Path Management section for more details.) The termination current level is programmable. To disable the charge current termination, the host sets the charge termination bit (TE) of charge control register to 0, refer to I2C section for details. A new charge cycle is initiated when one of the following conditions is detected: 1. The battery voltage falls below the VBATREG-VRCH threshold. 2. VSUPPLY toggle 3. CE bit toggle or RESET bit is set 4. HI-Z bit toggle Dynamic Power Path Management (DPPM) The bq2416x features a SYS output that powers the external system load connected to the battery. This output is active whenever a source is connected to IN, USB or BAT. The following sections discuss the behavior of SYS with a source connected to the supply or a battery source only. Input Source Connected When a valid input source is connected, the buck converter turns on to power the load on SYS. The STAT/INT pin outputs a 128s interrupt pulse to alert the host that an input has been connected. The FAULT bits indicate a normal condition, and the Supply Status register indicates that a new supply is connected. The CE bit (bit 1) in the control register (0x02) indicates whether a charge cycle is initiated. By default, the bq2416x (CE=0) enables a charge cycle when a valid input source is connected. When the CE bit is '1' and a valid input source is connected, the battery FET is turned off and the SYS output is regulated to the VSYS(REG) programmed by the VBATREG threshold in the I2C register. A charge cycle is initiated when the CE bit is written to a 0 value (cleared). Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 17 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com When the CE bit is a 0 and a valid source is connected to IN or USB, the buck converter starts up and a charge cycle is initiated. When VBAT is high enough that VSYS > VSYS(REG), the battery FET is turned on and the SYS output is connected to BAT. If the SYS voltage falls to VSYS(REG), it is regulated to that point to maintain the system output even with a deeply discharged or absent battery. In this mode, the SYS output voltage is regulated by the buck converter and the battery FET linearly regulates the charge current into the battery. The current from the supply is shared between charging the battery and powering the system load at SYS. The dynamic powerpath management (DPPM) circuitry of the bq2416x monitors the current limits continuously, and if the SYS voltage falls to the VMINSYS voltage, it adjusts charge current to maintain the minimum system voltage and supply the load on SYS. If the charge current is reduced to zero and the load increases further, the bq2416x enters battery-supplement mode. During supplement mode, the battery FET is turned on and the battery supplements the system load. 2000 mA 1800 mA ISYS 800 mA 0 mA 1500 IIN mA ~850 mA 0mA 1A IBAT 0mA -200 mA VSYS(REG) VMINSYS DPPM loop active VOUT ~3.1V Supplement Mode Figure 23. Example DPPM Response (VSupply=5V, VBAT = 3.1V, 1.5A Input current limit) VBAT(REG) should never be programmed less than VBAT. If the battery is ever 5% above the regulation threshold, the battery OVP circuit shuts the PWM converter off and the battery FET is turned on to discharge the battery to safe operating levels. Battery OVP errors are reported in the I2C status registers. Battery Only Connected When a battery voltage less than VBATUVLO is connected with no input source, the battery FET is turned on similar to supplement mode. In this mode, the current is not regulated; however, there is a short circuit current limit. If the short circuit limit is reached, the battery FET is turned off for the deglitch time. After the deglitch time, the battery FET is turned on to test and see if the short has been removed. If it has not, the FET turns off and the process repeats until the short is removed. This process is to protect the internal FET from over current. If an external FET is used for discharge, the body diode prevents the load on SYS from being disconnected from the battery. If the battery voltage is less than VBATUVLO, the battery FET (Q6) remains off and BAT is high-impedance. This prevents further discharging of deeply-discharged batteries. 18 Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 Battery Discharge FET (BGATE) The bq2416x contains a MOSFET driver to drive the gate of an external discharge FET between the battery and the system output. This external FET provides a low impedance path when supplying the system from the battery. Connect BGATE to the gate of the external discharge MOSFET. BGATE is on under the following conditions: 1. No input supply connected. 2. HZ_MODE = 1 3. CD pin connected high DEFAULT Mode DEFAULT mode is used when I2C communication is not available. DEFAULT mode is entered in the following situations: 1. When the charger is enabled and VBAT< VBATGD before I2C communication is established 2. When the watchdog timer expires without a reset from the I2C interface and the safety timer has not expired. 3. When the device comes out of any fault condition (sleep mode, OVP, faulty adapter mode, etc.) before I2C communication is established In DEFAULT mode, the I2C registers are reset to the default values. The 27-minute safety timer (no timer for bq24168) is reset and starts when DEFAULT mode is entered. The default value for VBATREG is 3.6V, and the default value for ICHARGE is 1A. The input current limit for the IN input is set to 1.5A. The input current limit for the USB input is determined by the D+/D- detection (bq24160/3) or PSEL (bq24161/8). PSEL and D+/D- detection have no effect on the IN input. Default mode is exited by programming the I2C interface. Once I2C communication is established, PSEL has no effect on the USB input. Note that if termination is enabled and charging has terminated, a new charge cycle is NOT initiated when entering DEFAULT mode. Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 19 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com Safety Timer and Watchdog Timer (bq24160/ bq24161/ bq24163 only) At the beginning of charging process, the bq24160/1/3 starts the safety timer. This timer is active during the entire charging process. If charging has not terminated before the safety timer expires, charging is halted and the CE bit is written to a "1". The length of the safety timer is selectable using the I2C interface. A single 128s pulse is sent on the STAT and INT outputs and the STATx bits of the status registers are updated in the I2C. In DEFAULT mode, the safety timer can be reset and a new charge initiated by removing/inserting the input supply or toggling the CD pin. In HOST mode, the CE bit is set to a '1' when the safety timer expires. The CE bit must be cleared to a '0' in order to resume charging and clear the safety timer fault. The safety timer duration is selectable using the TMR_X bits in the Safety Timer Register/ NTC Monitor register. Changing the safety timer duration resets the safety timer. This function prevents continuous charging of a defective battery. In addition to the safety timer, the bq24160/1/3 contain a watchdog timer that monitors the host through the I2C interface. Once a read/write is performed on the I2C interface, a 30-second timer (tWATCHDOG) is started. The 30second timer is reset by the host using the I2C interface. This is done by writing a "1" to the reset bit (TMR_RST) in the control register. The TMR_RST bit is automatically set to "0" when the 30-second timer is reset. This process continues until the battery is fully charged or the safety timer expires. If the 30-second timer expires, the IC enters DEFAULT mode where the default register values are loaded, the safety timer restarts at 27 minutes and charging continues. The I2C may be accessed again to reinitialize the desired values and restart the watchdog timer. The watchdog timer flow chart is shown in Figure 24. Start Safety Timer Safety timer expired? Yes Safety timer fault No Charge Done? ICHG < ITERM Yes STAT = Hi Update STAT bits Yes STAT = Hi Update STAT bits Charging suspended Enter suspended mode Fault indicated in STAT registers No No I2C Read/Write performed? Yes Start 30 second watchdog timer Charge Done? ICHG < ITERM Reset 30 second watchdog timer No Yes Safety timer fault Safety timer expired? No Charging suspended Fault indicated in STAT registers No 30s timer expired? Yes No Yes Received SW watchdog RESET? Reset to default values in I2C register Restart 27min safety timer Figure 24. The Watchdog Timer Flow Chart for bq2416x 20 Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 D+/D- Based Adapter Detection for the USB Input (D+/D-, bq24160/3) The bq24160/3 contain a D+/D- based adapter detection circuit that is used to program the input current limit for the USB input during DEFAULT mode. D+/D- detection is only performed in DEFAULT mode unless forced by the D+/D-_EN bit in host mode. By default the USB input current limit is set to 100mA. When USB is asserted the bq24160/3 performs a charger source identification to determine if it is connected to an SDP (USB port) or CDP/DCP (dedicated charger). When the detection is initated, the first step is the connection detection as described in BC1.2. This step detects when the D+/D- lines are connected to the bq24160/3. Once this connection is made, the circuit moves to the Primary Detection. If the connection detection has not completed within 500ms, the D+/D- detection selects 100mA for the unknown input source. The primary detection complies with the method described in BC1.2. During primary detection, the D+/D- lines are tested to determine if the port is an SDP or CDP/DCP. If a CDP/DCP is detected the input current limit is increased to 1.5A, if an SDP is detected the current limit remains at 100mA, until changed via the I2C interface. Secondary detection is not performed. Automatic detection is performed only if VD+ and VD- are less than 0.6V to avoid interfering with the USB transceiver which may also perform D+/D- detection when the system is running normally. However, D+/D- can be initiated at any time by the host by setting the D+/D- EN bit in the Control/Battery Voltage Register to 1. After detection is complete the D+/D- EN bit is automatically reset to 0 and the detection circuitry is disconnected from the D+/D- pins to avoid interference with USB data transfer. When a command is written to change the input current limit in the I2C, this overrides the current limit selected by D+/D- detection. D+/D- detection has no effect on the IN input. USB Input Current Limit Selector Input (PSEL, bq24161/8 only) The bq24161/8 contains a PSEL input that is used to program the input current limit for USB during DEFAULT mode. Drive PSEL high to indicate that a USB source is connected to the USB input and program the 100mA current limit for USB. Drive PSEL low to indicate that an AC Adapter is connected to the USB input. When PSEL is low, the IC starts up with a 1.5A current limit for USB. PSEL has no effect on the IN input. Once an I2C write is done, the PSEL has no effect on the input current limit until the watchdog timer expires. Hardware Chip Disable Input (CD) The bq2416x contains a CD input that is used to disable the IC and place the bq2416x into high-impedance mode. Drive CD low to enable charge and enter normal operation. Drive CD high to disable charge and place the bq2416x into high-impedance mode. Driving CD high during DEFAULT mode resets the safety timer. Driving CD high during HOST mode resets the safety timer and places the bq2416x into high impedance mode. The CD pin has precedence over the I2C control. LDO Output (DRV) The bq2416x contains a linear regulator (DRV) that is used to supply the internal MOSFET drivers and other circuitry. Additionally, DRV supplies up to 10mA external loads to power the STAT LED or the USB transceiver circuitry. The maximum value of the DRV output is 5.45V; ideal for protecting voltage sensitive USB circuits from high voltage fluctuations in the supply. The LDO is on whenever a supply is connected to the IN or USB inputs of the bq2416x. The DRV is disabled under the following conditions: 1. VSUPPLY < UVLO 2. VSUPPLY < VSLP 3. Thermal Shutdown Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 21 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com External NTC Monitoring (TS) The I2C interface allows the user to easily implement the JEITA standard for systems where the battery pack thermistor is monitored by the host. Additionally, the bq2416x provides a flexible, voltage based TS input for monitoring the battery pack NTC thermistor. The voltage at TS is monitored to determine that the battery is at a safe temperature during charging. The bq24160/3/8 enables the user to easily implement the JEITA standard for charging temperature while the bq24161 only monitors the hot and cold cutoff temperatures and leaves the JEITA control to the host. The JEITA specification is shown in. 1C 0.5C Portion of spec not covered by TS Implementation on bq24160 4.25 V 4.15 V 4.1 V T1 (0C) T2 (10C) T3 T4 (45C) (50C) T5 (60C) Figure 25. Charge Current During TS Conditions To satisfy the JEITA requirements, four temperature thresholds are monitored; the cold battery threshold (TNTC < 0C), the cool battery threshold (0C < TNTC < 10C), the warm battery threshold (45C < TNTC <L 60C) and the hot battery threshold (TNTC > 60C). These temperatures correspond to the VCOLD, VCOOL, VWARM, and VHOT thresholds. Charging is suspended and timers are suspended when VTS < VHOT or VTS > VCOLD. When VWARM < VTS < VHOT, the battery regulation voltage is reduced by 140mV from the programmed regulation threshold. When VCOLD < VTS < VCOOL, the charging current is reduced to half of the programmed charge current. The TS function is voltage based for maximum flexibility. Connect a resistor divider from DRV to GND with TS connected to the center tap to set the threshold. The connections are shown in Figure 31. The resistor values are calculated using the following equations: e 1 1 u VDRV RCOLD RHOT e u e VCOLD VHOT u RLO = eV u e V u RHOT e DRV - 1u - RCOLD e DRV - 1u V V e HOT u e COLD u (1) VDRV -1 VCOLD RHI = 1 1 + RLO RCOLD (2) Where: VCOLD = 0.60 x VDRV VHOT = 0.30 x VDRV 22 Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 Where RHOT is the NTC resistance at the hot temperature and RCOLD is the NTC resistance at cold temperature. For the bq24160/3/8, the WARM and COOL thresholds are not independently programmable. The COOL and WARM NTC resistances for a selected resistor divider are calculated using the following equations: RLO 0.564 RHI RCOOL = RLO - RLO 0.564 - RHI 0.564 (3) RLO 0.383 RHI RW ARM = RLO - RLO 0.383 - RHI 0.383 (4) VBAT(REG) 1 x Charge/ DISABLE -140 mV 0.5 x Charge TS COLD TS COOL VDRV + + TS WARM + VDRV TS HOT RHI + TS PACK+ TEMP bq2416x RLO PACK- Figure 26. TS Circuit Thermal Regulation and Protection During the charging process, to prevent chip overheating, the bq2416x monitors the junction temperature, TJ, of the die and begins to taper down the charge current once TJ reaches the thermal regulation threshold, TREG. The charge current is reduced to zero when the junction temperature increases about 10C above TREG. Once the charge current is reduced, the system current is reduced while the battery supplements the load to supply the system. This may cause a thermal shutdown of the bq2416x if the die temperature rises too high. At any state, if TJ exceeds TSHTDWN, the bq2416x suspends charging and disables the buck converter. During thermal shutdown mode, the buck converter is turned off, all timers are suspended, and a single 128s pulse is sent on the STAT and INT outputs and the STATx and FAULT_x bits of the status registers are updated in the I2C. A new charging cycle begins when TJ falls below TSHTDWN by approximately 10C. Input Voltage Protection in Charge Mode Sleep Mode The bq2416x enters the low-power sleep mode if the voltage on VSUPPLY falls below the sleep-mode entry threshold, VBAT+VSLP, and VSUPPLY is higher than the undervoltage lockout threshold, VUVLO. This feature prevents draining the battery during the absence of VSUPPLY. When VSUPPLY < VBAT+ VSLP, the bq2416x turns off the PWM converter, turns the battery FET on and drives BGATE to GND, sends a single 128s pulse on the STAT and INT outputs and updates the STATx and FAULT_x bits in the status registers. Once VSUPPLY > VBAT+ VSLP, the STATx and FAULT_x bits are cleared and the device initiates a new charge cycle. Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 23 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com Input Voltage Based DPM During normal charging process, if the input power source is not able to support the programmed or default charging current, the supply voltage decreases. Once the supply drops to VIN_DPM (default 4.2V for both inputs), the input current limit is reduced to prevent further supply droop. When the IC enters this mode, the charge current is lower than the set value and the DPM_STATUS bit is set (Bit 5 in Register 05H). This feature provides IC compatibility with adapters with different current capabilities without a hardware change. Figure 27 shows the VIN-DPM behavior to a current-limited source. In this figure the input source has a 750mA current limit and the charging is set to 750mA. The SYS load is then increased to 1.2A. Adapter Voltage Falls due to Adapter Current Limit VIN 5 V Adapter rated for 750 mA Input Current Reduced by VINDPM function to Prevent Adapter from Crashing IIN VSYS 750 mA Charging 750 mA Charging IBAT Supplement Mode 1.2 A Load Step ISYS Figure 27. bq24160 VIN-DPM Bad Source Detection When a source is connected to IN or USB, the bq2416x runs a Bad Source Detection procedure to determine if the source is strong enough to provide some current to charge the battery. A current sink is turned on (30mA for USB input, 75mA for the IN input) for 32ms. If the source is valid after the 32ms (VBADSOURCE < VSUPPLY < VOVP), the buck converter starts up and normal operation continues. If the supply voltage falls below VBAD_SOURCE during the detection, the current sink shuts off for two seconds and then retries, a single 128s pulse is sent on the STAT and INT outputs and the STATx and FAULT_x bits of the status registers and the battery/supply status registers are updated. The detection circuits retry continuously until either a new source is connected to the other input or a valid source is detected after the detection time. If during normal operation the source falls to VBAD_SOURCE, the bq2416x turns off the PWM converter, turns the battery FET on, sends a single 128s pulse is sent on the STAT and INT outputs and the STATx and FAULT_x bits of the status registers, and the battery/supply status registers are updated. Once a good source is detected, the STATx and FAULT_x bits are cleared and the device returns to normal operation. If two supplies are connected, the supply with precedence is checked first. If the supply detection fails once, the device switches to the other supply for two seconds and then retries. This allows the priority supply to settle if the connection was jittery or the supply ramp was too slow to pass detection. If the priority supply fails the detection a second time, it is locked out and lower priority supply is used. Once the bad supply is locked out, it remains locked out until the supply voltage falls below UVLO. This prevents continuously switching between a weak supply and a good supply. 24 Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 Input Overvoltage Protection The built-in input overvoltage protection to protect the device and other downstream components against damage from overvoltage on the input supply (Voltage from VUSB or VIN to PGND). During normal operation, if VSUPPLY > VOVP, the bq2416x turns off the PWM converter, turns the battery FET and BGATE on, sends a single 128s pulse is sent on the STAT and INT outputs and the STATx and FAULT_x bits of the status registers and the battery/supply status registers are updated. Once the OVP fault is removed, the STATx and FAULT_x bits are cleared and the device returns to normal operation. To allow operation with some unregulated adapters, the OVP circuit is not active during Bad Source Detection. This provides some time for the current sink to pull the unregulated adapter down into an acceptable range. If the adapter voltage is high at the end of the detection, the startup of the PWM converter does not occur. The OVP circuit is active during normal operation, so if the system standby current plus the charge current is not enough to pull down the source, operation is suspended. Charge Status Outputs (STAT, INT) The STAT output is used to indicate operation conditions for bq2416x. STAT is pulled low during charging when EN_STAT bit in the control register (0x02h) is set to "1". When charge is complete or disabled, STAT is high impedance. When a fault occurs, a 128-s pulse (interrupt) is sent out to notify the host. The status of STAT during different operation conditions is summarized in Table 1. STAT drives an LED for visual indication or can be connected to the logic rail for host communication. The EN_STAT bit in the control register (00H) is used to enable/disable the charge status for STAT. The interrupt pulses are unaffected by EN_STAT and will always be shown. The INT output is identical to STAT and is used to interface with a low voltage host processor. Table 1. STAT Pin Summary Charge State STAT and INT behavior Charge in progress and EN_STAT=1 Low Other normal conditions High-Impedance Status Changes: Supply Status Change (plug in or removal), safety timer fault, watchdog expiration, sleep mode, battery temperature fault (TS), battery fault (OVP or absent), thermal shutdown 128-s pulse, then High Impedance Good Battery Monitor The bq2416x contains a good battery monitor circuit that places the bq2416x into high-z mode if the battery voltage is above the BATGD threshold while in DEFAULT mode. This function is used to enable compliance to the battery charging standard that prevents charging from an un-enumerated USB host while the battery is above the good battery threshold. If the bq2416x is in HOST mode, it is assumed that USB host has been enumerated and the good battery circuit has no effect on charging. SERIAL INTERFACE DESCRIPTION The bq2416x uses an I2C-compatible interface to program charge parameters. I2C is a 2-wire serial interface developed by Philips Semiconductor (see I2C-Bus Specification, Version 2.1, January 2000). The bus consists of a data line (SDA) and a clock line (SCL) with pull-up structures. When the bus is idle, both SDA and SCL lines are pulled high. All I2C-compatible devices connect to the I2C bus through open drain I/O pins, SDA and SCL. A master device, usually a microcontroller or a digital signal processor, controls the bus. The master is responsible for generating the SCL signal and device addresses. The master also generates specific conditions that indicate the START and STOP of data transfer. A slave device receives and/or transmits data on the bus under control of the master device. The bq2416x device works as a slave and supports the following data transfer modes, as defined in the I2C Bus Specification: standard mode (100kbps) and fast mode (400kbps). The interface adds flexibility to the battery charging solution, enabling most functions to be programmed to new values depending on the instantaneous application requirements. Register contents remain intact as long as battery voltage remains above 2.5V (typical). The I2C circuitry is powered from VBUS when a supply is connected. If the VBUS supply is not connected, the I2C circuitry is powered from the battery through BAT. The battery voltage must stay above 2.5V with no input connected in order to maintain proper operation. Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 25 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com The data transfer protocol for standard and fast modes is exactly the same; therefore, they are referred to as the F/S-mode in this document. The bq2416x devices only support 7-bit addressing. The device 7-bit address is defined as `1101011' (6Bh). F/S Mode Protocol The master initiates data transfer by generating a start condition. The start condition is when a high-to-low transition occurs on the SDA line while SCL is high, as shown in Figure 28. All I2C-compatible devices should recognize a start condition. DATA CLK S P START Condition STOP Condition Figure 28. START and STOP Condition The master then generates the SCL pulses, and transmits the 8-bit address and the read/write direction bit R/W on the SDA line. During all transmissions, the master ensures that data is valid. A valid data condition requires the SDA line to be stable during the entire high period of the clock pulse (see Figure 29). All devices recognize the address sent by the master and compare it to their internal fixed addresses. Only the slave device with a matching address generates an acknowledge (see Figure 30) by pulling the SDA line low during the entire high period of the ninth SCL cycle. Upon detecting this acknowledge, the master knows that communication link with a slave has been established. DATA CLK Data Line Stable Data Valid Chang of Data Allowed Figure 29. Bit Transfer on the Serial Interface The master generates further SCL cycles to either transmit data to the slave (R/W bit 1) or receive data from the slave (R/W bit 0). In either case, the receiver needs to acknowledge the data sent by the transmitter. So an acknowledge signal can either be generated by the master or by the slave, depending on which one is the receiver. The 9-bit valid data sequences consisting of 8-bit data and 1-bit acknowledge can continue as long as necessary. To signal the end of the data transfer, the master generates a stop condition by pulling the SDA line from low to high while the SCL line is high (see Figure 31). This releases the bus and stops the communication link with the addressed slave. All I2C compatible devices must recognize the stop condition. Upon the receipt of a stop condition, all devices know that the bus is released, and wait for a start condition followed by a matching address. If a transaction is terminated prematurely, the master needs sending a STOP condition to prevent the slave I2C logic from remaining in an incorrect state. Attempting to read data from register addresses not listed in this section result in FFh being read out. 26 Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 Data Output by Transmitter Not Acknowledge Data Output by Receiver Acknowledge SCL From Master 1 2 8 9 S Clock Pulse for Acknowledgement START Condition Figure 30. Acknowledge on the I2C Bus Recognize START or REPRATED START Condition Recognize STOP or REPRATED START Condition Generate ACKNOWLEDGE Signal P SDA Acknowledgment Signal From Slave MSB Sr Address R/W SCL S or Sr ACK ACK Sr or P Clock Line Held Low While Interrupts are Serviced Figure 31. Bus Protocol Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 27 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com REGISTER DESCRIPTION Status/Control Register (READ/WRITE) Memory location: 00, Reset state: 0xxx 0xxx BIT NAME Read/Write FUNCTION B7 (MSB) TMR_RST Read/Write Write: TMR_RST function, write "1" to reset the watchdog timer (auto clear) Read: Always 0 (bq24160/1/3 only) B6 STAT_2 Read only B5 STAT_1 Read only B4 STAT_0 Read only 000001010011100101110111- B3 SUPPLY_SEL Read/Write 0-IN has precedence when both supplies are connected 1-USB has precedence when both supplies are connected (default 0) B2 FAULT_2 Read only B1 FAULT_1 Read only B0 (LSB) FAULT_0 Read only 000-Normal 001- Thermal Shutdown 010- Battery Temperature Fault 011- Watchdog Timer Expired (bq24160/1/3 only) 100- Safety Timer Expired (bq24160/1/3 only) 101- IN Supply Fault 110- USB Supply Fault 111- Battery Fault No Valid Source Detected IN Ready (shows preferred source when both connected) USB Ready (shows preferred source when both connected) Charging from IN Charging from USB Charge Done NA Fault SUPPLY_SEL Bit (Supply Precedence Selector) The SUPPLY_SEL bit selects which supply has precedence when both supplies are present. In cases where both supplies are connected, they must remain isolated from each other which means only one is allowed to charge the battery. Write a "1" to SUPPLY_SEL to select the USB input to have precedence. Write a "0" to select the IN input. Battery/ Supply Status Register (READ/WRITE) Memory location: 01, Reset state: xxxx 0xxx BIT NAME Read/Write FUNCTION B7 (MSB) INSTAT1 Read Only B6 INSTAT0 Read Only 00-Normal 01-Supply OVP 10-Weak Source Connected (No Charging) 11- VIN<VUVLO B5 USBSTAT1 Read Only B4 USBSTAT0 Read Only B3 OTG_LOCK Read/Write 0 - No OTG supply present. Use USB input as normal. 1 - OTG supply present. Lockout USB input for charging. (default 0) B2 BATSTAT1 Read Only B1 BATSTAT0 Read Only 00-Battery Present and Normal 01-Battery OVP 10-Battery Not Present 11- NA B0 (LSB) EN_NOBATOP Read/ Write 28 Submit Documentation Feedback 00-Normal 01-Supply OVP 01-Weak Source Connected (No Charging) 11- VUSB<VUVLO 0-Normal Operation 1-Enables No Battery Operation when termination is disabled (default 0) Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 OTG_LOCK Bit (USB Lockout) The OTG_LOCK bit is used to prevent any charging from USB input regardless of the SUPPLY_SEL bit and IN supply status. For systems using OTG supplies, it is not desirable to charge from an OTG source. Doing so would mean draining the battery by allowing it to effectively charge itself. Write a "1" to OTG_LOCK to lock out the USB input. Write a "0" to OTG_LOCK to return to normal operation. During OTG lock, the USB input is ignored and DRV does not come up. The watchdog timer must be reset while in USB_LOCK to maintain the USB lockout state. This prevents the USB input from being permanently locked out for cases where the host loses I2C communication with OTG_LOCK set (i.e., discharged battery from OTG operation). See the Safety Timer and Watchdog Timer section for more details. EN_NOBATOP (No Battery Operation with Termination Disabled) The EN_NOBATOP bit is used to enable operation when termination is disabled and no battery is connected. This is useful for cases where the PA is connected to the BAT pin and it desired to do a GSM calibration in the factory. For this application, the TE bit (Bit 2 in Register 0x02h) should be set to a "0" to disable termination and the EN_NOBATOP should be set to a "1". This feature should not be used during normal operation as it disables the BATOVP and the reverse boost protection circuits. Control Register (READ/WRITE) Memory location: 02, Reset state: 1000 1100 BIT NAME Read/Write B7 (MSB) RESET Write only Write: 1 - Reset all registers to default values 0 - No effect Read: always get "1" B6 IUSB_LIMIT_2 Read/Write B5 IUSB_LIMIT_1 Read/Write B4 IUSB_LIMIT _0 Read/Write 000 - USB2.0 host with 100mA current limit 001 - USB3.0 host with 150mA current limit 010 - USB2.0 host with 500mA current limit 011 - USB host/charger with 800mA current limit 100 - USB3.0 host with 900mA current limit 101 - USB host/charger with 1500mA current limit 110-111 - NA (default 000 (1)) B3 EN_STAT Read/Write 1 - Enable STAT output to show charge status, 0-Disable STAT output for charge status. Fault interrupts are still show even when EN_STAT = 0. (default 1) B2 TE Read/Write 1 - Enable charge current termination, 0-Disable charge current termination (default 1) B1 CE Read/Write 1 - Charging is disabled 0 - Charging enabled (default 0) B0 (LSB) HZ_MODE Read/Write 1 - High impedance mode 0 - Not high impedance mode (default 0) (1) FUNCTION When in DEFAULT mode, the D+/D- (bq24160) or PSEL (bq24161/8) inputs determine the input current limit for the USB input. RESET Bit The RESET bit in the control register (0x02h) is used to reset all the charge parameters. Write "1" to RESET bit to reset all the registers to default values and place the bq2416x into DEFAULT mode and turn off the watchdog timer. The RESET bit is automatically cleared to zero once the bq2416x enters DEFAULT mode. CE Bit (Charge Enable) The CE bit in the control register (0x02h) is used to disable or enable the charge process. A low logic level (0) on this bit enables the charge and a high logic level (1) disables the charge. When charge is disabled, the SYS output regulates to VSYS(REG) and battery is disconnected from the SYS. Supplement mode is still available if the system load demands cannot be met by the supply. Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 29 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com HZ_MODE Bit (High Impedance Mode Enable) The HZ_MODE bit in the control register (0x02h) is used to disable or enable the high impedance mode. A low logic level (0) on this bit enables the IC and a high logic level (1) puts the IC in a low quiescent current state called high impedance mode. When in high impedance mode, the converter is off and the battery FET and BGATE are on. The load on SYS is supplied by the battery. Control/Battery Voltage Register (READ/WRITE) Memory location: 03, Reset state: 0001 0100 * BIT NAME Read/Write FUNCTION B7 (MSB) VBREG5 Read/Write Battery Regulation Voltage: 640 mV (default 0) B6 VBREG4 Read/Write Battery Regulation Voltage: 320 mV (default 0) B5 VBREG3 Read/Write Battery Regulation Voltage: 160 mV (default 0) B4 VBREG2 Read/Write Battery Regulation Voltage: 80 mV (default 1) B3 VBREG1 Read/Write Battery Regulation Voltage: 40 mV (default 0) B2 VBREG0 Read/Write Battery Regulation Voltage: 20 mV (default 1) B1 IINLIMIT Read/Write Input Limit for IN input0 - 1.5A 1 - 2.5A (default 0) B0 (LSB) D+/D-_EN Read/Write 0 - Normal state, D+/D- Detection done 1 - Force D+/D- Detection. Returns to "0" after detection is done. (default 0) Charge voltage range is 3.5V-4.44V with the offset of 3.5V and step of 20mV (default 3.6V). Vender/Part/Revision Register (READ only) Memory location: 04, Reset state: 0100 0000 30 BIT NAME Read/Write B7 (MSB) Vender2 Read only Vender Code: bit 2 (default 0) B6 Vender1 Read only Vender Code: bit 1 (default 1) B5 Vender0 Read only Vender Code: bit 0 (default 0) B4 PN1 Read only B3 PN0 Read only For I2C Address 6Bh: 00: bq2416x 01-11: Future product spins B2 Revision2 Read only B1 Revision1 Read only B0 (LSB) Revision0 Read only Submit Documentation Feedback FUNCTION 000: Revision 1.0 001: Revision 1.1 010: Revision 2.0 011: Revision 2.1 100: Revision 2.2 101: Revision 2.3 110-111: Future Revisions Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 Battery Termination/Fast Charge Current Register (READ/WRITE) Memory location: 05, Reset state: 0011 0010 * * BIT NAME Read/Write FUNCTION B7 (MSB) ICHRG4 Read/Write Charge current: 1200mA - (default 0) B6 ICHRG3 Read/Write Charge current: 600mA - (default 0) B5 ICHRG2 Read/Write Charge current: 300mA - (default 1) B4 ICHRG1 Read/Write Charge current: 150mA - (default 1) B3 ICHRG0 Read/Write Charge current: 75 mA (default 0) B2 ITERM2 Read/Write Termination current sense voltage: 200mA (default 0) B1 ITERM1 Read/Write Termination current sense voltage: 100mA (default 1) B0 (LSB) ITERM0 Read/Write Termination current sense voltage: 50mA (default 0) Charge current sense offset is 550mA and default charge current is 1000mA. Termination threshold offset is 50mA and default termination current is 150mA VIN-DPM Voltage/ DPPM Status Register Memory location: 06, Reset state: xx00 0000 * BIT NAME Read/Write FUNCTION B7(MSB) MINSYS_STATUS Read Only 1 - Minimum System Voltage mode is active (low battery condition) 0 - Minimum System Voltage mode is not active B6 DPM_STATUS Read Only 1 - VIN-DPM mode is active 0 - VIN-DPM mode is not active B5 VINDPM2(USB) Read/Write USB input VIN-DPM voltage: 320mV (default 0) B4 VINDPM1(USB) Read/Write USB input VIN-DPM voltage: 160mV (default 0) B3 VINDPM0(USB) Read/Write USB input VIN-DPM voltage: 80mV (default 0) B2 VINDPM2(IN) Read/Write IN input VIN-DPM voltage: 320mV (default 0) B1 VINDPM1(IN) Read/Write IN input VIN-DPM voltage: 160mV (default 0) B0(LSB) VINDPM0(IN) Read/Write IN input VIN-DPM voltage: 80mV (default 0) VIN-DPM voltage offset is 4.20V and default VIN-DPM threshold is 4.20V. Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 31 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com Safety Timer/ NTC Monitor Register (READ/WRITE) Memory location: 07, Reset state: 1001 1xxx BIT NAME Read/Write FUNCTION B7 (MSB) 2XTMR_EN Read/Write 1 - Timer slowed by 2x when in thermal regulation, input current limit, VIN_DPM or DPPM 0 - Timer not slowed at any time (default 0) (bq24160/1 only) B6 TMR_1 Read/Write B5 TMR_2 Read/Write Safety Timer Time Limit - 00 - 27 minute fast charge 01 - 6 hour fast charge 10 - 9 hour fast charge 11 - Disable safety timers (default 00) (bq24160/1 only) B4 NA Read/Write NA B3 TS_EN Read/Write 0 - TS function disabled 1 - TS function enabled (default 1) B2 TS_FAULT1 Read only B1 TS_FAULT0 Read only TS Fault Mode: 00 - Normal, No TS fault 01 - TS temp < TCOLD or TS temp > THOT(Charging suspended) 10 - TCOOL > TS temp > TCOLD (Charge current reduced by half, bq24160 only) 11 - TWARM < TS temp < THOT (Charge voltage reduced by 140mV, bq24160 only) B0 (LSB) LOW_CHG Read/ Write 0 - Charge current as programmed in Register 0x05 1 - Charge current is half programmed value in Register 0x05 (default 0) 2xTMR_EN Bit (2x Timer Enable) The 2xTMR_EN bit is used to slow down the timer when charge current is reduced by the system load. When 2xTMR_EN is a "1", the safety timer is slowed to half speed effectively doubling the timer time. The conditions that activate the 2x timer are: Input Current Limit, VINDPM, Thermal Regulation, LOW_CHG, BATSHRT and TS Cool. When 2xTMR_EN is a "0", the timer operates at normal speed in all conditions. LOW_CHG Bit (Low Charge Mode Enable) The LOW_CHG bit is used to reduce the charge current from the programmed value. This feature is used by systems where battery NTC is monitored by the host and requires a reduced charge current setting or by systems that need a "preconditioning" current for low battery voltages. Write a "1" to this bit to charge at half of the programmed charge current (bq24160/1/3/8). Write a "0" to this bit to charge at the programmed charge current. 32 Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 APPLICATION INFORMATION Output Inductor and Capacitor Selection Guidelines When selecting an inductor, several attributes must be examined to find the right part for the application. First, the inductance value should be selected. The bq2416x is designed to work with 1.5H to 2.2H inductors. The chosen value will have an effect on efficiency and package size. Due to the smaller current ripple, some efficiency gain is reached using the 2.2H inductor, however, due to the physical size of the inductor, this may not be a viable option. The 1.5H inductor provides a good tradeoff between size and efficiency. Once the inductance has been selected, the peak current must be calculated in order to choose the current rating of the inductor. Use Equation 5 to calculate the peak current. ae % o IPEA K = ILOAD(MAX) c1+ RIPPP LE / 2 e o (5) The inductor selected must have a saturation current rating greater than or equal to the calculated IPEAK. Due to the high currents possible with the bq2416x, a thermal analysis must also be done for the inductor. Many inductors have a 40C temperature-rise rating. The DC component of the current can cause a 40C temperature rise above the ambient temperature in the inductor. For this analysis, the typical load current may be used adjusted for the duty cycle of the load transients. For example, if the application requires a 1.5A DC load with peaks at 2.5A 20% of the time, a 40C temperature rise current must be greater than 1.7A: ITEMPRISE = ILOAD + D (IPEAK - ILOAD ) = 1.5A + 0.2 x (2.5A - 1 .5A ) = 1.7A (6) The bq2416x provides internal loop compensation. Using this scheme, the bq2416x is stable with 10F to 200F of local capacitance on the SYS output. The capacitance on the SYS rail can be higher if distributed amongst the rail. To reduce the output voltage ripple, a ceramic capacitor with the capacitance between 10F and 47F is recommended for local bypass to SYS. A 47F bypass capacitor is recommended for optimal transient response. Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 33 bq24160, bq24161 bq24163, bq24168 SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 www.ti.com PCB Layout Guidelines It is important to pay special attention to the PCB layout. Figure 32 provides a sample layout for the high current paths of the bq2416x. A list of layout guidelines follows. IN PMIDU USB PMIDI SW PGND PGND BOOT SYS BAT SW SYS Figure 32. Recommended bq2416x PCB Layout for WCSP * * * * * * * * 34 To obtain optimal performance, the power input capacitors, connected from the PMID input to PGND, must be placed as close as possible to the bq2416x Minimize the amount of inductance between BAT and the postive connection of the battery terminal. If a large parasitic board inductance on BAT is expected, increase the bypass capacitance on BAT. Place 4.7F input capacitor as close to PMID_ pin and PGND pin as possible to make high frequency current loop area as small as possible. Place 1F input capacitor GNDs as close to the respective PMID cap GND and PGND pins as possible to minimize the ground difference between the input and PMID_. The local bypass capacitor from SYS to GND should be connected between the SYS pin and PGND of the IC. The intent is to minimize the current path loop area from the SW pin through the LC filter and back to the PGND pin. Place all decoupling capacitors close to their respective IC pins and as close as to PGND (do not place components such that routing interrupts power stage currents). All small control signals should be routed away from the high-current paths. The PCB should have a ground plane (return) connected directly to the return of all components through vias (two vias per capacitor for power-stage capacitors, one via per capacitor for small-signal components). It is also recommended to put vias inside the PGND pads for the IC, if possible. A star ground design approach is typically used to keep circuit block currents isolated (high-power/low-power small-signal) which reduces noisecoupling and ground-bounce issues. A single ground plane for this design gives good results. With this small layout and a single ground plane, there is no ground-bounce issue, and having the components segregated minimizes coupling between signals. The high-current charge paths into IN, USB, BAT, SYS and from the SW pins must be sized appropriately for the maximum charge current in order to avoid voltage drops in these traces. The PGND pins should be connected to the ground plane to return current through the internal low-side FET. For high-current applications, the balls for the power paths should be connected to as much copper in the board as possible. This allows better thermal performance because the board conducts heat away from the IC. Submit Documentation Feedback Copyright (c) 2011-2012, Texas Instruments Incorporated Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 bq24160, bq24161 bq24163, bq24168 www.ti.com SLUSAO0A - NOVEMBER 2011 - REVISED MARCH 2012 Changes from Original (November 2011) to Revision A Page * Changed VBATREG - Voltage regulation accuracy .................................................................................................................. 5 * Changed the USB Pin numbers in the YFF pachkage for bq24160/3 From: A5-A6 To: A5-A7 ......................................... 11 * Changed Figure 3 ............................................................................................................................................................... 11 * Changed Figure 4 ............................................................................................................................................................... 12 Copyright (c) 2011-2012, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): bq24160 bq24161 bq24163 bq24168 35 PACKAGE OPTION ADDENDUM www.ti.com 31-Aug-2012 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/ Ball Finish MSL Peak Temp (3) (Requires Login) BQ24160RGER ACTIVE VQFN RGE 24 3000 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR BQ24160RGET ACTIVE VQFN RGE 24 250 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR BQ24160YFFR ACTIVE DSBGA YFF 49 3000 Green (RoHS & no Sb/Br) SNAGCU Level-1-260C-UNLIM BQ24160YFFT ACTIVE DSBGA YFF 49 250 Green (RoHS & no Sb/Br) SNAGCU Level-1-260C-UNLIM BQ24161RGER ACTIVE VQFN RGE 24 3000 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR BQ24161RGET ACTIVE VQFN RGE 24 250 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR BQ24161YFFR ACTIVE DSBGA YFF 49 3000 Green (RoHS & no Sb/Br) SNAGCU Level-1-260C-UNLIM BQ24161YFFT ACTIVE DSBGA YFF 49 250 Green (RoHS & no Sb/Br) SNAGCU Level-1-260C-UNLIM BQ24163RGER ACTIVE VQFN RGE 24 3000 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR BQ24163RGET ACTIVE VQFN RGE 24 250 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR BQ24163YFFR PREVIEW DSBGA YFF 49 3000 TBD Call TI Call TI BQ24163YFFT PREVIEW DSBGA YFF 49 250 TBD Call TI Call TI BQ24168RGER ACTIVE VQFN RGE 24 3000 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR BQ24168RGET ACTIVE VQFN RGE 24 250 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR BQ24168YFFR ACTIVE DSBGA YFF 49 3000 Green (RoHS & no Sb/Br) SNAGCU Level-1-260C-UNLIM BQ24168YFFT ACTIVE DSBGA YFF 49 250 Green (RoHS & no Sb/Br) SNAGCU Level-1-260C-UNLIM (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. Addendum-Page 1 Samples PACKAGE OPTION ADDENDUM www.ti.com 31-Aug-2012 NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. Addendum-Page 2 PACKAGE MATERIALS INFORMATION www.ti.com 31-Aug-2012 TAPE AND REEL INFORMATION *All dimensions are nominal Device BQ24160RGER Package Package Pins Type Drawing VQFN RGE 24 BQ24160RGET VQFN RGE BQ24160YFFR DSBGA YFF BQ24160YFFT DSBGA BQ24161RGER SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant 3000 330.0 12.4 4.25 4.25 1.15 8.0 12.0 Q2 24 250 180.0 12.4 4.25 4.25 1.15 8.0 12.0 Q2 49 3000 180.0 8.4 2.93 2.93 0.81 4.0 8.0 Q1 YFF 49 250 180.0 8.4 2.93 2.93 0.81 4.0 8.0 Q1 VQFN RGE 24 3000 330.0 12.4 4.25 4.25 1.15 8.0 12.0 Q2 BQ24161RGET VQFN RGE 24 250 180.0 12.4 4.25 4.25 1.15 8.0 12.0 Q2 BQ24161YFFR DSBGA YFF 49 3000 180.0 8.4 2.93 2.93 0.81 4.0 8.0 Q1 BQ24161YFFT DSBGA YFF 49 250 180.0 8.4 2.93 2.93 0.81 4.0 8.0 Q1 BQ24163RGER VQFN RGE 24 3000 330.0 12.4 4.25 4.25 1.15 8.0 12.0 Q2 BQ24163RGET VQFN RGE 24 250 180.0 12.4 4.25 4.25 1.15 8.0 12.0 Q2 BQ24168RGER VQFN RGE 24 3000 330.0 12.4 4.25 4.25 1.15 8.0 12.0 Q2 BQ24168RGET VQFN RGE 24 250 180.0 12.4 4.25 4.25 1.15 8.0 12.0 Q2 BQ24168YFFR DSBGA YFF 49 3000 180.0 8.4 2.93 2.93 0.81 4.0 8.0 Q1 BQ24168YFFT DSBGA YFF 49 250 180.0 8.4 2.93 2.93 0.81 4.0 8.0 Q1 Pack Materials-Page 1 PACKAGE MATERIALS INFORMATION www.ti.com 31-Aug-2012 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) BQ24160RGER VQFN RGE 24 3000 367.0 367.0 35.0 BQ24160RGET VQFN RGE 24 250 210.0 185.0 35.0 BQ24160YFFR DSBGA YFF 49 3000 210.0 185.0 35.0 BQ24160YFFT DSBGA YFF 49 250 210.0 185.0 35.0 BQ24161RGER VQFN RGE 24 3000 367.0 367.0 35.0 BQ24161RGET VQFN RGE 24 250 210.0 185.0 35.0 BQ24161YFFR DSBGA YFF 49 3000 210.0 185.0 35.0 BQ24161YFFT DSBGA YFF 49 250 210.0 185.0 35.0 BQ24163RGER VQFN RGE 24 3000 367.0 367.0 35.0 BQ24163RGET VQFN RGE 24 250 210.0 185.0 35.0 BQ24168RGER VQFN RGE 24 3000 367.0 367.0 35.0 BQ24168RGET VQFN RGE 24 250 210.0 185.0 35.0 BQ24168YFFR DSBGA YFF 49 3000 210.0 185.0 35.0 BQ24168YFFT DSBGA YFF 49 250 210.0 185.0 35.0 Pack Materials-Page 2 X: Max = 2.791 mm, Min = 2.69 mm Y: Max = 2.791 mm, Min = 2.69 mm IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. 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