XC9235/XC9236/XC9237 Series ETR0514-013 600mA Driver Tr. Built-In, Synchronous Step-Down DC/DC Converters GreenOperation Compatible GENERAL DESCRIPTION The XC9235/XC9236/XC9237 series is a group of synchronous-rectification type DC/DC converters with a built-in 0.42 P-channel MOS driver transistor and 0.52N-channel MOS switching transistor, designed to allow the use of ceramic capacitors. Operating voltage range is from 2.0V to 6.0V (AC types), 1.8V to 6.0V (DG types). For the D/F types which have a reference voltage of 0.8V (accuracy: 2.0%), the output voltage can be set from 0.9V by using two external resistors. The A/B/C/E/G types have a fixed output voltage from 0.8V to 4.0V in increments of 0.05V (accuracy: 2.0%). The device provides a high efficiency, stable power supply with an output current of 600mA to be configured using only a coil and two capacitors connected externally. With the built-in oscillator, either 1.2MHz or 3.0MHz can be selected for suiting to your particular application. As for operation mode, the XC9235 series is PWM control, the XC9236 series is automatic PWM/PFM switching control and the XC9237 series can be manually switched between the PWM control mode and the automatic PWM/PFM switching control mode, allowing fast response, low ripple and high efficiency over the full range of loads (from light load to heavy load). The soft start and current control functions are internally optimized. During stand-by, all circuits are shutdown to reduce current consumption to as low as 1.0A or less. The B/F/G types have a high speed soft-start as fast as 0.25ms in typical for quick turn-on. With the built-in UVLO (Under Voltage Lock Out) function, the internal P-channel MOS driver transistor is forced OFF when input voltage becomes 1.4V or lower. The B to G types integrate CL discharge function which enables the electric charge at the output capacitor CL to be discharged via the internal discharge switch located between the LX and VSS pins. When the devices enter stand-by mode, output voltage quickly returns to the VSS level as a result of this function. Four types of package SOT-25, USP-6C, USP-6EL and WLP-5-03 are available. APPLICATIONS Mobile phones, Smart phones Bluetooth headsets Mobile WiMAX PDAs, MIDs, UMPCs Portable game consoles Digital cameras, Camcorders MP3 Players, Portable Media Players Notebook computers TYPICAL APPLICATION CIRCUIT XC9235/XC9236/XC9237 A/B/C/E/G types (Output Voltage Fixed) FEATURES Driver Transistor Built-In : 0.42 P-ch driver transistor 0.52 N-ch switch transistor Input Voltage : 2.0V ~ 6.0V (A/B/C types) 1.8V ~ 6.0V (D/E/F/G types) Output Voltage : 0.8V ~ 4.0V (Internally set) 0.9V ~ 6.0V (Externally set) High Efficiency : 92% (TYP.)* Output Current : 600mA Oscillation Frequency : 1.2MHz, 3.0MHz (+15%) Maximum Duty Cycle : 100% Control Methods : PWM (XC9235) PWM/PFM Auto (XC9236) PWM/PFM Manual (XC9237) Function : Current Limiter Circuit Built-In (Constant Current & Latching) CL Discharge (B/C/D/E/F/G types) High Speed Soft Start (B/F/G type) Capacitor : Low ESR Ceramic Capacitor Operating Ambient Temperature :-40 ~ +85 Packages : SOT-25 (A/B/C types only) USP-6C USP-6EL(A/B/C types only) WLP-5-03(A/B types only) Environmentally Friendly : EU RoHS Compliant, Pb Free * Performance depends on external components and wiring on the PCB. TYPICAL PERFORMANCE CHARACTERISTICS XC9235/XC9236/XC9237 Efficiency vs. Output CurrentfOSC=1.2MHz, VOUT=1.8V D/F types (Output Voltage Externally Set) 100 PWM/PFM Automatic Sw itching Control 90 Efficiency: EFFI (%) Efficency:EFFI(%) 80 VIN= 4.2V 70 60 50 PWM Control VIN= 4.2V 3.6V 2.4V 3.6V 2.4V 40 30 20 10 0 0.1 1 10 100 1000 Output Current:IOUT(mA) 1/34 XC9235/XC9236/XC9237 Series PIN CONFIGURATION Lx VOUT 5 4 1 2 VIN VSS VIN 6 1 Lx VSS 5 2 VSS CE/MODE 4 3 VOUT (FB) VIN 6 1 Lx VSS 5 2 VSS CE/MODE 4 3 VOUT 3 CE/MODE SOT-25 SOT-25 (TOP VIEW) (Top View) USP-6C (BOTTOM VIEW) USP-6EL (BOTTOM VIEW) * Please short the VSS pin (No. 2 and 5). * The dissipation pad for the USP-6C package should be solder-plated in recommended mount pattern and metal masking so as to enhance mounting strength and heat release. If the pad needs to be connected to other pins, it should be connected to the VSS (No. 5) pin. WLP-5-03 (BOTTOM VIEW) PIN ASSIGNMENT 2/34 SOT-25 1 2 3 PIN NUMBER USP-6C/USP-6EL 6 2, 5 4 WLP-5-03 2 3 1 4 3 4 5 1 5 PIN NAME FUNCTIONS VIN VSS CE / MODE VOUT FB Lx Power Input Ground High Active Enable / Mode Selection Pin Fixed Output Voltage Pin (A/B/C/E/G types) Output Voltage Sense Pin (D/F types) Switching Output XC9235/XC9236/XC9237 Series PRODUCT CLASSIFICATION Ordering Information XC9235-(*1) XC9236-(*1) *1 XC9237-( ) DESIGNATOR ITEM Fixed Output voltage (VOUT) Functional selection Adjustable Output voltage (FB) Functional selection - Fixed PWM control PWM / PFM automatic switching control Fixed PWM control QPWM / PFM automatic switching manual selection SYMBOL VIN2.0V, No CL discharge, Low speed soft-start VIN2.0V, CL discharge, High speed soft-start C VIN2.0V, CL discharge, Low speed soft-start E VIN1.8V, CL discharge, Low speed soft-start G VIN1.8V, CL discharge, High speed soft-start D VIN1.8V, CL discharge, Low speed soft-start F VIN1.8V, CL discharge, High speed soft-start Output voltage options e.g. VOUT=2.8V=2, =8 VOUT=2.85V=2, =L 0.05V increments: 0.05=A, 0.15=B, 0.25=C, 0.35=D, 0.45=E, 0.55=F, 0.65=H, 0.75=K, 0.85=L, 0.95=M Reference voltage is fixed in 0.8V =0, =8 Fixed Output Voltage (VOUT) 08 ~ 40 Adjustable Output Voltage (FB) 08 Oscillation Frequency Packages (Order Unit) DESCRIPTION A B C D 1.2MHz 3.0MHz MR SOT-25(*2) (3,000/Reel) MR-G SOT-25(*2) (3,000/Reel) ER USP-6C (3,000/Reel) ER-G USP-6C (3,000/Reel) 4R-G USP-6EL(*2) (3,000/Reel) 0R-G WLP-5-03 (*3) (3,000/Reel) (*1) The "-G" suffix denotes Halogen and Antimony free as well as being fully RoHS compliant. SOT-25, USP-6EL package are available for the A/B/C series only. (*3) WLP-5-03 package is available for the A/B series only. (*2) 3/34 XC9235/XC9236/XC9237 Series BLOCK DIAGRAM XC9235 / XC9236 / XC9237 XC9235 / XC9236 / XC9237 A Series B/C/E/G Series XC9235 / XC9236 / XC9237 D/F Series NOTE: The signal from CE/MODE Control Logic to PWM/PFM Selector is being fixed to "L" level inside, and XC9235 series chooses only PWM control. The signal from CE/MODE Control Logic to PWM/PFM Selector is being fixed to "H" level inside, and XC9236 series chooses only PWM/PFM automatic switching control. Diodes inside the circuit are ESD protection diodes and parasitic diodes. ABSOLUTE MAXIMUM RATINGS Ta=25 PARAMETER SYMBOL RATINGS UNIT VIN Pin Voltage Lx Pin Voltage VOUT Pin Voltage FB Pin Voltage CE / MODE Pin Voltage Lx Pin Current SOT-25 USP-6C Power Dissipation USP-6EL WLP-5-03 Operating Ambient Temperature Storage Temperature VIN VLx VOUT VFB VCE ILx - 0.3 ~ 6.5 - 0.3 ~ VIN + 0.3 - 0.3 ~ 6.5 - 0.3 ~ 6.5 - 0.3 ~ 6.5 1500 250 120 120 750 - 40 ~ + 85 - 55 ~ + 125 V V V V V mA 4/34 Pd Topr Tstg mW O O C C XC9235/XC9236/XC9237 Series ELECTRICAL CHARACTERISTICS XC9235A18Cxx/XC9236A18Cxx/XC9237A18Cxx, VOUT=1.8V, fOSC=1.2MHz, Ta=25 PARAMETER SYMBOL Output Voltage VOUT Operating Voltage Range VIN CONDITIONS When connected to external components, VIN=VCE=5.0V, IOUT=30mA Maximum Output Current IOUTMAX VIN=VOUT(E)+2.0V, VCE=1.0V, (*9) When connected to external components UVLO Voltage VUVLO VCE =VIN, VOUT=0V, (*1, *11) Voltage which Lx pin holding "L" level MIN. TYP. MAX. UNIT CIRCUIT 1.764 1.800 1.836 V 2.0 - 6.0 V 600 - - mA 1.00 1.40 1.78 V Supply Current IDD VIN=VCE=5.0V, VOUT=VOUT(E)x1.1V - 15 33 A Stand-by Current ISTB VIN=5.0V, VCE=0V, VOUT=VOUT(E)x1.1V - 0 1.0 A Oscillation Frequency fOSC When connected to external components, VIN=VOUT(E)+2.0V, VCE =1.0V, IOUT=100mA 1020 1200 1380 kHz PFM Switching Current IPFM When connected to external components, (*12) VIN=VOUT(E)+2.0V, VCE =VIN, IOUT=1mA 120 160 200 mA PFM Duty Limit DTYLIMIT_PFM Maximum Duty Cycle DTYMAX VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V Minimum Duty Cycle DTYMIN VIN=VCE=5.0V, VOUT=VOUT(E)x1.1V When connected to external components, VCE=VIN=VOUT(E)+1.2V, IOUT=100mA (*3) VIN=VCE=5.0V, VOUT=0V, ILx=100mA Efficiency (*2) EFFI Lx SW "H" ON Resistance 1 RLxH VCE=VIN=(C-1), IOUT=1mA (*12) (*3) 200 300 % 100 - - % - - 0 % - 92 - % - 0.35 0.55 Lx SW "H" ON Resistance 2 RLxH VIN=VCE=3.6V, VOUT=0V, ILx=100mA - 0.42 0.67 Lx SW "L" ON Resistance 1 RLxL VIN=VCE=5.0V (*4) - 0.45 0.65 Lx SW "L" ON Resistance 2 RLxL VIN=VCE=3.6V (*4) - 0.52 0.77 - - 0.01 1.0 A Lx SW "H" Leak Current (*5) ILEAKH VIN=VOUT=5.0V, VCE=0V, Lx=0V Lx SW "L" Leak Current (*5) ILEAKL VIN=VOUT=5.0V, VCE=0V, Lx=5.0V (*10) Current Limit Output Voltage Temperature Characteristics CE "H" Voltage CE "L" Voltage (*8) ILIM VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V VOUT/ IOUT=30mA, -40Topr85 (VOUTTopr) VOUT=0V, Applied voltage to VCE, VCEH (*11) Voltage changes Lx to "H" level VOUT=0V, Applied voltage to VCE , VCEL (*11) Voltage changes Lx to "L" level PWM "H" Level Voltage VPWMH PWM "L" Level Voltage VPWML CE "H" Current CE "L" Current ICEH ICEL Soft Start Time tSS Latch Time tLAT Short Protection Threshold Voltage VSHORT When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes 1020 kHzfOSC1380kHz When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes fOSC1020kHz VIN=VCE=5.0V, VOUT=0V VIN=5.0V, VCE=0V, VOUT=0V When connected to external components, VCE=0V VIN, IOUT=1mA VIN=VCE=5.0V, VOUT=0.8xVOUT(E), (*7) Short Lx at 1 resistance Sweeping VOUT, VIN=VCE=5.0V, Short Lx at 1 resistance, VOUT voltage which Lx becomes "L" level within 1ms - 0.01 1.0 A 900 1050 1350 mA - 100 - ppm/ 0.65 - 6.0 V VSS - 0.25 V - - VIN - 1.0 V VIN - 0.25 - - V - 0.1 - 0.1 - 0.1 0.1 A A 0.5 1.0 2.5 ms 1.0 - 20.0 ms 0.675 0.900 1.150 V Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage NOTE: *1: Including hysteresis operating voltage range. *2: EFFI = { ( output voltagexoutput current ) / ( input voltagexinput current) }x100 *3: ON resistance ()= (VIN - Lx pin measurement voltage) / 100mA *4: R&D value *5: When temperature is high, a current of approximately 10A (maximum) may leak. *6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation, control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH. *7: Time until it short-circuits VOUT with GND via 1of resistor from an operational state and is set to Lx=0V from current limit pulse generating. *8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance. *9: When the difference between the input and the output is small, some cycles may be skipped completely before current maximizes. If current is further pulled from this state, output voltage will decrease because of P-ch driver ON resistance. *10: Current limit denotes the level of detection at peak of coil current. *11: "H"=VIN~VIN-1.2V, "L"=+0.1V~-0.1V *12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control's functions. *13: XC9235/XC9236 series exclude VPWMH and VPWML because those are only for the XC9237 series' functions. 5/34 XC9235/XC9236/XC9237 Series ELECTRICAL CHARACTERISTICS (Continued) XC9235A18Dxx/XC9236A18Dxx/XC9237A18Dxx, VOUT=1.8V, fOSC=3.0MHz, Ta=25 PARAMETER SYMBOL Output Voltage VOUT Operating Voltage Range VIN CONDITIONS When connected to external components, VIN=VCE=5.0V, IOUT=30mA Maximum Output Current IOUTMAX VIN=VOUT(E)+2.0V, VCE=1.0V, (*9) When connected to external components UVLO Voltage VUVLO VCE=VIN, VOUT=0V, (*1,*11) Voltage which Lx pin holding "L" level MIN. TYP. MAX. UNIT CIRCUIT 1.764 1.800 1.836 V 2.0 - 6.0 V 600 - - mA 1.00 1.40 1.78 V Supply Current IDD VIN=VCE=5.0V, VOUT=VOUT(E)x1.1V - 21 35 A Stand-by Current ISTB VIN=5.0V, VCE=0V, VOUT=VOUT(E)x1.1V - 0 1.0 A Oscillation Frequency fOSC When connected to external components, VIN=VOUT(E)+2.0V, VCE=1.0V, IOUT=100mA 2550 3000 3450 kHz PFM Switching Current IPFM When connected to external components, (*12) VIN=VOUT(E)+2.0V, VCE=VIN, IOUT=1mA 170 220 270 mA PFM Duty Limit DTYLIMIT_PFM Maximum Duty Cycle DTYMAX VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V Minimum Duty Cycle DTYMIN VIN=VCE=5.0V, VOUT=VOUT(E)x0.1V When connected to external components, VCE=VINVOUT(E)+1.2V, IOUT=100mA (*3) VIN=VCE=5.0V, VOUT =0V, ILx=100mA (*3) VIN=VCE=3.6V, VOUT =0V, ILx=100mA (*4) VIN=VCE=5.0V (*4) VIN=VCE=3.6V VIN=VOUT=5.0V, VCE=0V, Lx=0V VIN=VOUT=5.0V, VCE=0V, Lx=5.0V (*8) VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V Efficiency (*2) EFFI VCE=VIN=(C-1), IOUT=1mA (*12) Lx SW "H" ON Resistance 1 RLxH Lx SW "H" ON Resistance 2 RLxH Lx SW "L" ON Resistance 1 RLxL Lx SW "L" ON Resistance 2 RLxL (*5) Lx SW "H" Leak Current ILEAKH (*5) Lx SW "L" Leak Current ILEAKL (*10) Current Limit ILIM Output Voltage VOUT/ IOUT=30mA, -40Topr85 Temperature Characteristics (VOUTTopr) VOUT=0V, Applied voltage to VCE, CE "H" Voltage VCEH (*11) Voltage changes Lx to "H" level VOUT=0V, Applied voltage to VCE, CE "L" Voltage VCEL (*11) Voltage changes Lx to "L" level PWM "H" Level Voltage VPWMH PWM "L" Level Voltage VPWML CE "H" Current CE "L" Current ICEH ICEL Soft Start Time tSS Latch Time tLAT Short Protection Threshold Voltage VSHORT When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes 2550kHzfOSC3450kHz When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes fOSC2550kHz VIN=VCE=5.0V, VOUT=0V VIN=5.0V, VCE=0V, VOUT=0V When connected to external components, VCE=0V VIN, IOUT=1mA VIN=VCE=5.0V, VOUT=0.8xVOUT(E), (*7) Short Lx at 1 resistance Sweeping VOUT, VIN=VCE=5.0V, Short Lx at 1 resistance, VOUT voltage which Lx becomes "L" level within 1ms - 200 300 % 100 - - % - - 0 % - 86 - % 900 0.35 0.42 0.45 0.52 0.01 0.01 1050 0.55 0.67 0.65 0.77 1.0 1.0 1350 A A mA - 100 - ppm/ 0.65 - 6.0 V VSS - 0.25 V - - VIN - 1.0 V VIN - 0.25 - - V - 0.1 - 0.1 - 0.1 0.1 A A 0.5 0.9 2.5 ms 1.0 - 20 ms 0.675 0.900 1.150 V Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage NOTE: *1: Including hysteresis operating voltage range. *2: EFFI = { ( output voltagexoutput current ) / ( input voltagexinput current) }x100 *3: ON resistance ()= (VIN - Lx pin measurement voltage) / 100mA *4: R&D value *5: When temperature is high, a current of approximately 10A (maximum) may leak. *6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation, control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH. *7: Time until it short-circuits VOUT with GND via 1of resistor from an operational state and is set to Lx=0V from current limit pulse generating. *8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance. *9: When the difference between the input and the output is small, some cycles may be skipped completely before current maximizes. If current is further pulled from this state, output voltage will decrease because of P-ch driver ON resistance. *10: Current limit denotes the level of detection at peak of coil current. *11: "H"=VIN~VIN-1.2V, "L"=+0.1V~-0.1V *12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control's functions. *13: XC9235/XC9236 series exclude VPWMH and VPWML because those are only for the XC9237 series' functions. 6/34 XC9235/XC9236/XC9237 Series ELECTRICAL CHARACTERISTICS (Continued) XC9235B(C)(E)(G)18Cxx/XC9236B(C)(E)(G)18Cxx/XC9237B(C)(E)(G)18Cxx, VOUT=1.8V, fOSC=1.2MHz, Ta=25 PARAMETER SYMBOL Output Voltage VOUT Operating Voltage Range (B/C series) Operating Voltage Range (E/G series) VIN Maximum Output Current IOUTMAX UVLO Voltage VUVLO Supply Current Stand-by Current IDD ISTB Oscillation Frequency fOSC PFM Switching Current IPFM CONDITIONS When connected to external components, VIN=VCE=5.0V, IOUT=30mA VIN=VOUT(E)+2.0V, VCE=1.0V, (*9) When connected to external components (*14) VCE =VIN, VOUT=VOUT(E)x0.5V (*1, *11) Voltage which Lx pin holding "L" level VIN=VCE=5.0V, VOUT=VOUT(E)x1.1V VIN=5.0V, VCE=0V, VOUT=VOUT(E)x1.1V When connected to external components, VIN=VOUT(E)+2.0V, VCE =1.0V, IOUT=100mA When connected to external components, (*12) VIN=VOUT(E)+2.0V, VCE =VIN, IOUT=1mA (*12) VCE=VIN=(C-1), IOUT=1mA PFM Duty Limit DTYLIMIT_PFM Maximum Duty Cycle DTYMAX VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V Minimum Duty Cycle DTYMIN MIN. TYP. MAX. UNIT CIRCUIT 1.764 1.800 1.836 V 2.0 1.8 - 6.0 6.0 V 600 - - mA 1.00 1.40 1.78 V - 15 0 33 1.0 A A 1020 1200 1380 kHz 120 160 200 mA 200 300 % 100 - - % - - 0 % - 92 - % - 0.35 0.55 (*3) - 0.42 0.67 - 0.45 0.65 Lx SW "H" ON Resistance 1 RLxH VIN=VCE=5.0V, VOUT=VOUT(E)x1.1V When connected to external components, VCE=VIN=VOUT(E)+1.2V, IOUT=100mA (*3) VIN=VCE=5.0V, VOUT (E)x0.9V , ILx=100mA Lx SW "H" ON Resistance 2 RLxH VIN=VCE=3.6V, VOUT (E)x0.9V , ILx=100mA Lx SW "L" ON Resistance 1 RLxL VIN=VCE=5.0V (*4) RLxL VIN=VCE=3.6V (*4) - 0.52 0.77 - ILEAKH VIN=VOUT=5.0V, VCE=0V, Lx=0V - 0.01 1.0 A 900 1050 1350 mA - 100 - ppm/ 0.65 - 6.0 V VSS - 0.25 V - - VIN - 1.0 V VIN - 0.25 - - V - 0.1 - 0.1 - 0.1 0.1 A A - 0.25 0.40 ms 0.5 1.0 2.5 ms 1.0 - 20.0 ms 0.675 0.900 1.150 V 0.338 0.450 0.563 V 200 300 450 Efficiency (*2) EFFI Lx SW "L" ON Resistance 2 Lx SW "H" Leak Current (*5) (*10) Current Limit Output Voltage Temperature Characteristics CE "H" Voltage CE "L" Voltage (*8) ILIM VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V VOUT/ I =30mA, -40Topr85 (VOUTTopr) OUT VOUT= VOUT(E)x0.9V, Applied voltage to VCE, VCEH (*11) Voltage changes Lx to "H" level VOUT= VOUT(E)x0.9V, Applied voltage to VCE , VCEL (*11) Voltage changes Lx to "L" level PWM "H" Level Voltage VPWMH PWM "L" Level Voltage VPWML CE "H" Current CE "L" Current ICEH ICEL Soft Start Time (B/G Series) tSS Soft Start Time (C/E Series) tSS Latch Time tLAT Short Protection Threshold Voltage (B/C Series) VSHORT Short Protection Threshold Voltage (E/G Series) VSHORT CL Discharge RDCHG When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes 1020 kHzfOSC1380kHz When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes fOSC1020kHz VIN=VCE=5.0V, VOUT= VOUT(E)x0.9V VIN=5.0V, VCE=0V, VOUT= VOUT(E)x0.9V When connected to external components, VCE=0V VIN, IOUT=1mA When connected to external components, VCE=0V VIN, IOUT=1mA VIN=VCE=5.0V, VOUT=0.8xVOUT(E), (*7) Short Lx at 1 resistance Sweeping VOUT, VIN=VCE=5.0V, Short Lx at 1 resistance, VOUT voltage which Lx becomes "L" level within 1ms (*11) VIN=VCE=5.0V, The VOUT at Lx="Low" while decreasing VOUT from VOUT (E)x0.4V VIN=5.0V, LX=5.0V, VCE=0V, VOUT=open Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage, applied voltage sequence is VOUTVINVCE NOTE: *1: Including hysteresis operating voltage range. *2: EFFI = { ( output voltagexoutput current ) / ( input voltagexinput current) }x100 *3: ON resistance ()= (VIN - Lx pin measurement voltage) / 100mA *4: R&D value *5: When temperature is high, a current of approximately 10A (maximum) may leak. *6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation, control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH. *7: Time until it short-circuits VOUT with GND via 1of resistor from an operational state and is set to Lx=0V from current limit pulse generating. *8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance. *9: When the difference between the input and the output is small, some cycles may be skipped completely before current maximizes. If current is further pulled from this state, output voltage will decrease because of P-ch driver ON resistance. *10: Current limit denotes the level of detection at peak of coil current. *11: "H"=VIN~VIN-1.2V, "L"=+0.1V~-0.1V *12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control's functions. *13: XC9235/XC9236 series exclude VPWMH and VPWML because those are only for the XC9237 series' functions. *14: VIN is applied when VOUT (E) x 0.5V becomes more than VIN. 7/34 XC9235/XC9236/XC9237 Series ELECTRICAL CHARACTERISTICS (Continued) XC9235B(C)(E)(G)18Dxx/XC9236B(C)(E)(G)18Dxx/XC9237B(C)(E)(G)18Dxx, VOUT=1.8V, fOSC=3.0MHz, Ta=25 PARAMETER SYMBOL Output Voltage VOUT Operating Voltage Range (B/C series) Operating Voltage Range (E/G series) VIN Maximum Output Current IOUTMAX UVLO Voltage VUVLO Supply Current Stand-by Current IDD ISTB Oscillation Frequency fOSC PFM Switching Current IPFM CONDITIONS When connected to external components, VIN=VCE=5.0V, IOUT=30mA VIN=VOUT(E)+2.0V, VCE=1.0V, (*9) When connected to external components (*14) , VCE=VIN, VOUT=VOUT(E)x0.5V (*1,*11) Voltage which Lx pin holding "L" level VIN=VCE=5.0V, VOUT=VOUT(E)x1.1V VIN=5.0V, VCE=0V, VOUT=VOUT(E)x1.1V When connected to external components, VIN=VOUT(E)+2.0V, VCE=1.0V, IOUT=100mA When connected to external components, (*12) VIN=VOUT(E)+2.0V, VCE=VIN, IOUT=1mA (*12) VCE=VIN=(C-1), IOUT=1mA PFM Duty Limit DTYLIMIT_PFM Maximum Duty Cycle DTYMAX VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V Minimum Duty Cycle DTYMIN VIN=VCE=5.0V, VOUT=VOUT(E)x0.1V When connected to external components, VCE=VINVOUT(E)+1.2V, IOUT=100mA (*3) VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V, ILx=100mA (*3) VIN=VCE=3.6V, VOUT=VOUT(E)x0.9V, ILx=100mA (*4) VIN=VCE=5.0V (*4) VIN=VCE=3.6V VIN=VOUT=5.0V, VCE=0V, Lx=0V (*8) VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V (*2) Efficiency Lx SW "H" ON Resistance 1 Lx SW "H" ON Resistance 2 Lx SW "L" ON Resistance 1 Lx SW "L" ON Resistance 2 (*5) Lx SW "H" Leak Current (*10) Current Limit Output Voltage Temperature Characteristics CE "H" Voltage CE "L" Voltage EFFI RLxH RLxH RLxL RLxL ILEAKH ILIM VOUT/ I =30mA, -40Topr85 (VOUTTopr) OUT VOUT=VOUT(E)x0.9V, Applied voltage to VCE, VCEH (*11) Voltage changes Lx to "H" level VOUT=VOUT(E)x0.9V, Applied voltage to VCE, VCEL (*11) Voltage changes Lx to "L" level When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes 2550kHzfOSC3450kHz PWM "H" Level Voltage VPWMH PWM "L" Level Voltage VPWML CE "H" Current CE "L" Current ICEH ICEL Soft Start Time (B/G Series) tSS Soft Start Time (C/E Series) tSS Latch Time tLAT Short Protection Threshold Voltage (B/C Series) VSHORT Short Protection Threshold Voltage (E/G Series) VSHORT VIN=VCE=5.0V, The VOUT at Lx="Low" decreasing VOUT from VOUT (E)x0.4V CL Discharge RDCHG VIN=5.0V, LX=5.0V, VCE=0V, VOUT=open When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes fOSC2550kHz VIN=VCE=5.0V, VOUT=VOUT(E)x0.9V VIN=5.0V, VCE=0V, VOUT=VOUT(E)x0.9V When connected to external components, VCE=0V VIN, IOUT=1mA When connected to external components, VCE=0V VIN, IOUT=1mA VIN=VCE=5.0V, VOUT=0.8xVOUT(E), (*7) Short Lx at 1 resistance Sweeping VOUT, VIN=VCE=5.0V, Short Lx at 1 resistance, VOUT voltage which Lx becomes "L" level within 1ms (*11) while MIN. TYP. MAX. UNIT CIRCUIT 1.764 1.800 1.836 V 2.0 1.8 - 6.0 6.0 V 600 - - mA 1.00 1.40 1.78 V - 21 0 35 1.0 A A 2550 3000 3450 kHz 170 220 270 mA - 200 300 % 100 - - % - - 0 % - 86 - % 900 0.35 0.42 0.45 0.52 0.01 1050 0.55 0.67 0.65 0.77 1.0 1350 A mA - 100 - ppm/ 0.65 - 6.0 V VSS - 0.25 V - - VIN - 1.0 V VIN - 0.25 - - V - 0.1 - 0.1 - 0.1 0.1 A A - 0.32 0.50 ms 0.5 0.9 2.5 ms 1.0 - 20 ms 0.675 0.900 1.150 V 0.338 0.450 0.563 V 200 300 450 Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage, applied voltage sequence is VOUTVINVCE NOTE: *1: Including hysteresis operating voltage range. *2: EFFI = { ( output voltagexoutput current ) / ( input voltagexinput current) }x100 *3: ON resistance ()= (VIN - Lx pin measurement voltage) / 100mA *4: R&D value *5: When temperature is high, a current of approximately 10A (maximum) may leak. *6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation, control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH. *7: Time until it short-circuits VOUT with GND via 1of resistor from an operational state and is set to Lx=0V from current limit pulse generating. *8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance. *9: When the difference between the input and the output is small, some cycles may be skipped completely before current maximizes. If current is further pulled from this state, output voltage will decrease because of P-ch driver ON resistance. *10: Current limit denotes the level of detection at peak of coil current. *11: "H"=VIN~VIN-1.2V, "L"=+0.1V~-0.1V *12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control's functions. *13: XC9235/XC9236 series exclude VPWMH and VPWML because those are only for the XC9237 series' functions. *14: VIN is applied when VOUT (E) x 0.5V becomes more than VIN. 8/34 XC9235/XC9236/XC9237 Series ELECTRICAL CHARACTERISTICS (Continued) XC9235D(F)08Cxx/XC9236D(F)08Cxx/XC9237D(F)08Cxx, FB Type, fOSC=1.2MHz, Ta=25 PARAMETER SYMBOL CONDITIONS (*11) FB Voltage VFB Operating Voltage Range VIN Maximum Output Current IOUTMAX UVLO Voltage VUVLO Supply Current Stand-by Current IDD ISTB Oscillation Frequency fOSC PFM Switching Current IPFM VIN = VCE =5.0V, The VFB at Lx="High" decreasing FB pin voltage from 0.9V. while VIN=3.2V, VCE=1.0V (*9) When connected to external components VCE = VIN , VFB = 0.4V, (*1,*11) Voltage which Lx pin holding "L" level VIN =VCE=5.0V, VFB= 0.88V VIN =5.0V, VCE=0V, VFB= 0.88V When connected to external components, VIN = 3.2V, VCE=1.0V, IOUT=100mA When connected to external components, (*12) VIN =3.2V, VCE = VIN , IOUT=1mA (*12) VCE= VIN =2.0V IOUT=1mA PFM Duty Limit DTYLIMIT_PFM Maximum Duty Cycle DTYMAX VIN = VCE =5.0V, VFB = 0.72V Minimum Duty Cycle DTYMIN VIN = VCE =5.0V, VFB = 0.88V When connected to external components, VCE = VIN 2.4V, IOUT = 100mA (*3) VIN = VCE = 5.0V, VFB = 0.72V,ILX = 100mA (*3) VIN = VCE = 3.6V, VFB = 0.72V,ILX = 100mA (*4) VIN = VCE = 5.0V (*4) VIN = VCE = 3.6V VIN = VFB = 5.0V, VCE = 0V, LX= 0V (*8) VIN = VCE= 5.0V, VFB = 0.72V IOUT =30mA -40Topr85 VFB =0.72V, Applied voltage to VCE, (*11) Voltage changes Lx to "H" level VFB =0.72V, Applied voltage to VCE, (*11) Voltage changes Lx to "L" level When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes 1020kHzfOSC1380kHz When connected to external components, (*6) IOUT=1mA , Voltage which oscillation frequency (*13) becomes fOSC1020kHz VIN = VCE =5.0V, VFB =0.72V VIN =5.0V, VCE = 0V, VFB =0.72V When connected to external components, VCE = 0V VIN , IOUT=1mA VIN=VCE=5.0V, VFB=0.64, Short Lx at 1 (*7) resistance (*11) while VIN = VCE =5.0V, The VFB at Lx="Low" decreasing FB pin voltage from 0.4V. Efficiency (*2) EFFI Lx SW "H" ON Resistance 1 Lx SW "H" ON Resistance 2 Lx SW "L" ON Resistance 1 Lx SW "L" ON Resistance 2 (*5) Lx SW "H" Leak Current (*10) Current Limit Output Voltage Temperature Characteristics RLH RLH RLL RLL ILEAKH ILIM VOUT/ (VOUTTopr) CE "H" Voltage VCEH CE "L" Voltage VCEL PWM "H" Level Voltage VPWMH PWM "L" Level Voltage VPWML CE "H" Current CE "L" Current Soft Start Time (D series) Soft Start Time (F series) ICEH ICEL Latch Time tLAT Short Protection Threshold Voltage VSHORT CL Discharge RDCHG tSS VIN = 5.0V ,LX = 5.0V, VCE = 0V, VFB= open MIN. TYP. MAX. UNIT CIRCUIT 0.784 0.800 0.816 V 1.8 - 6.0 V 600 - - mA 1.00 1.40 1.78 V - 15 0 1.0 A A 1020 1200 1380 kHz 120 160 200 mA 200 300 % 100 - - % - - 0 % - 92 - % 900 0.35 0.42 0.45 0.52 0.01 1050 0.55 0.67 0.65 0.77 1.0 1350 A mA - 100 - ppm/ 0.65 - 6.0 V VSS - 0.25 V - - VIN - 1.0 V VIN 0.25 - - V - 0.1 - 0.1 0.5 - 1.0 0.25 0.1 0.1 2.5 0.40 A A ms 1.0 - 20.0 ms 0.15 0.200 0.25 V 200 300 450 Test conditions: VOUT=1.2V when the external components are connected. Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage, applied voltage sequence is VOUTVINVCE NOTE: *1: Including hysteresis operating voltage range. *2: EFFI = { ( output voltagexoutput current ) / ( input voltagexinput current) }x100 *3: ON resistance ()= (VIN - Lx pin measurement voltage) / 100mA *4: R&D value *5: When temperature is high, a current of approximately 10A (maximum) may leak. *6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation, control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH. *7: Time until it short-circuits VFB with GND via 1of resistor from an operational state and is set to Lx=0V from current limit pulse generating. *8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance. *9: When the difference between the input and the output is small, some cycles may be skipped completely before current maximizes. If current is further pulled from this state, output voltage will decrease because of P-ch driver ON resistance. *10: Current limit denotes the level of detection at peak of coil current. *11: "H"=VIN~VIN-1.2V, "L"=+0.1V~-0.1V *12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control's functions. *13: XC9235/XC9236 series exclude VPWMH and VPWML because those are only for the XC9237 series' functions. 9/34 XC9235/XC9236/XC9237 Series ELECTRICAL CHARACTERISTICS (Continued) XC9235D(F)08Dxx/XC9236D(F)08Dxx/XC9237D(F)08Dxx, FB, fOSC=3.0MHz, Ta=25 PARAMETER SYMBOL FB Voltage VFB Operating Voltage Range VIN CONDITIONS (*11) VIN = VCE =5.0V, The VFB at Lx="High" decreasing FB pin voltage from 0.9V. while Maximum Output Current IOUTMAX VIN=3.2V, VCE=1.0V (*9) When connected to external components UVLO Voltage VUVLO VCE = VIN , VFB = 0.4V , (*1, *11) Voltage which Lx pin holding "L" level MIN. TYP. MAX. UNIT CIRCUIT 0.784 0.800 0.816 V 1.8 - 6.0 V 600 - - mA 1.00 1.40 1.78 V Supply Current IDD VIN =VCE=5.0V, VFB= 0.88V - 21 35 A Stand-by Current ISTB - 0 1.0 A Oscillation Frequency fOSC 2550 3000 3450 kHz PFM Switching Current IPFM VIN =5.0V, VCE=0V, VFB= 0.88V When connected to external components, VIN = 3.2V, VCE=1.0V, IOUT=100mA When connected to external components, (*12) VIN =3.2V, VCE = VIN , IOUT=1mA 170 220 270 mA (*12) PFM Duty Limit DTYLIMIT_PFM Maximum Duty Cycle DTYMAX VIN = VCE =5.0V, VFB = 0.72V Minimum Duty Cycle DTYMIN VIN = VCE =5.0V, VFB = 0.88V When connected to external components, VCE = VIN 2.4V, IOUT = 100mA (*3) VIN = VCE = 5.0V, VFB = 0.72V,ILX = 100mA (*3) VIN = VCE = 3.6V, VFB = 0.72V,ILX = 100mA (*4) VIN = VCE = 5.0V (*4) VIN = VCE = 3.6V VIN = VFB = 5.0V, VCE = 0V, LX= 0V (*8) VIN = VCE= 5.0V, VFB = 0.72V IOUT =30mA -40Topr85 VFB =0.72V , VCE, (*11) Voltage changes Lx to "H" level VFB =0.72V, VCE, (*11) Voltage changes Lx to "L" level When connected to external components, (*6) IOUT = 1mA , Voltage which oscillation frequency (*13) becomes 2550kHzfOSC3450kHz When connected to external components, (*6) IOUT = 1mA , Voltage which oscillation frequency (*13) becomes fOSC2550kHz VIN = VCE =5.0V, VFB =0.72V VIN =5.0V, VCE = 0V, VFB =0.72V When connected to external components, VCE = 0V VIN , IOUT=1mA VIN = VCE = 5.0V, VFB = 0.64, (*7) Short Lx at 1 resistance (*11) VIN = VCE =5.0V, The VFB at Lx="Low" while decreasing FB pin voltage from 0.4V. Efficiency (*2) EFFI Lx SW "H" ON Resistance 1 Lx SW "H" ON Resistance 2 Lx SW "L" ON Resistance 1 Lx SW "L" ON Resistance 2 (*5) Lx SW "H" Leak Current (*10) Current Limit Output Voltage Temperature Characteristics RLH RLH RLL RLL ILEAKH ILIM VOUT/ (VOUTTopr) CE "H" Voltage VCEH CE "L" Voltage VCEL PWM "H" Level Voltage VPWMH PWM "L" Level Voltage VPWML CE "H" Current CE "L" Current Soft Start Time (D series) Soft Start Time (F series) ICEH ICEL Latch Time tLAT Short Protection Threshold Voltage VSHORT CL Discharge RDCHG tSS VCE= VIN =2.2V IOUT=1mA VIN = 5.0V ,LX = 5.0V ,VCE = 0V ,VFB= open 200 300 % 100 - - % - - 0 % - 86 - % 900 0.35 0.42 0.45 0.52 0.01 1050 0.55 0.67 0.65 0.77 1.0 1350 A mA - 100 - ppm/ 0.65 - 6.0 V VSS - 0.25 V - - VIN - 1.0 V VIN 0.25 - - V - 0.1 - 0.1 0.5 - 1.0 0.25 0.1 0.1 2.5 0.40 A A ms 1.0 - 20.0 ms 0.15 0.200 0.25 V 200 300 450 Test conditions: VOUT=1.2V when the external components are connected. Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage, applied voltage sequence is VOUTVINVCE NOTE: *1: Including hysteresis operating voltage range. *2: EFFI = { ( output voltagexoutput current ) / ( input voltagexinput current) }x100 *3: ON resistance ()= (VIN - Lx pin measurement voltage) / 100mA *4: R&D value *5: When temperature is high, a current of approximately 10A (maximum) may leak. *6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation, control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH. *7: Time until it short-circuits VFB with GND via 1of resistor from an operational state and is set to Lx=0V from current limit pulse generating. *8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance. *9: When the difference between the input and the output is small, some cycles may be skipped completely before current maximizes. If current is further pulled from this state, output voltage will decrease because of P-ch driver ON resistance. *10: Current limit denotes the level of detection at peak of coil current. *11: "H"=VIN~VIN-1.2V, "L"=+0.1V~-0.1V *12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control's functions. *13: XC9235/XC9236 series exclude VPWMH and VPWML because those are only for the XC9237 series' functions. 10/34 XC9235/XC9236/XC9237 Series ELECTRICAL CHARACTERISTICS (Continued) PFM Switching Current (IPFM) by Oscillation Frequency and Setting Voltage (mA) SETTING VOLTAGE VOUT(E) 1.2V 1.2VVOUT(E) 1.75V 1.8VVOUT(E) MIN. 1.2MHz TYP. MAX. 140 130 120 180 170 160 240 220 200 MIN. 3.0MHz TYP. MAX. 190 180 170 260 240 220 350 300 270 Input Voltage (VIN) for Measuring PFM Duty Limit (DTYLIMIT_PFM) fOSC C-1 1.2MHz VOUT(E)+0.5V 3.0MHz VOUT(E)+1.0V Minimum operating voltage is 2.0V. ex.) Although when VOUT(E) is 1.2V and fOSC is 1.2MHz, (C-1) should be 1.7V, (C-1) becomes 2.0V for the minimum operating voltage 2.0V. Soft-Start Time, Setting VoltageXC9235B(G)/XC9236B(G)/XC9237B(G) Series only SERIES XC9235B(G)/XC9237B(G) XC9236B(G) XC9235B(G)/ XC9236B(G)/XC9237B(G) (s) fOSC SETTING VOLTAGE MIN. TYP. MAX. 1.2MHz 1.2MHz 0.8V OUT(E)<1.5 - 250 400 1.5V OUT(E)<1.8 - 320 500 1.2MHz 1.8V OUT(E)<2.5 - 250 400 1.2MHz 2.5V OUT(E)<4.0 - 320 500 1.2MHz 0.8V OUT(E)<2.5 - 250 400 1.2MHz 2.5V OUT(E)<4.0 - 320 500 3.0MHz 0.8V OUT(E)<1.8 - 250 400 3.0MHz 1.8V OUT(E)<4.0 - 320 500 11/34 XC9235/XC9236/XC9237 Series TYPICAL APPLICATION CIRCUIT XC9235/XC9236/XC9237A, B, C, E, G Series (Output Voltage Fixed) VOUT 600mA L VIN Lx VSS VIN VSS C IN (ceramic) CL (ceramic) VOUT CE/ MODE CE/MODE fOSC=3.0MHz L: 1.5H CIN: 4.7F CL: 10F fOSC=1.2MHz L: 4.7H CIN: 4.7F CL: 10F (NR3015, TAIYO YUDEN) (Ceramic) (Ceramic) (NR4018, TAIYO YUDEN) (Ceramic) (Ceramic) XC9235/XC9236/XC9237D, F Series (Output Voltage External Setting) <Setting for Output Voltage> Output voltage can be set externally by adding two resistors to the FB pin. The output voltage is calculated by the RFB1 and RFB2 value. The total of RFB1 and RFB2 is usually selected less than 1M. Output voltages can be set in the range of 0.9V to 0.6V by use of 0.8V2.0% reference voltage. However, when input voltage (VIN) is lower than the setting output voltage, output voltage (VOUT) can not be higher than the input voltage (VIN). VOUT=0.8 x (RFB1+RFB2)/RFB2 The value of the phase compensation speed-up capacitor CFB is calculated by the formula of fZFB = 1/(2xxCFBxRFB1) with fZFB <10kHz. For optimization, fZFB can be adjusted in the range of 1kHz to 20kHz depending on the inductance L and the load capacitance CL which are used. Formula When RFB1=470k and RFB2=150k, VOUT1=0.8 x (470k+150k) / 150k=3.3V Example VOUT RFB1 (V) (k) 0.9 100 1.2 150 1.5 130 1.8 300 12/34 RFB2 (k) 820 300 150 240 CFB (pF) 150 100 220 150 VOUT (V) 2.5 3.0 3.3 4.0 RFB1 (k) 510 330 470 120 RFB2 (k) 240 120 150 30 CFB (pF) 100 150 100 470 XC9235/XC9236/XC9237 Series OPERATIONAL DESCRIPTION The XC9235/XC9236/XC9237 series consists of a reference voltage source, ramp wave circuit, error amplifier, PWM comparator, phase compensation circuit, output voltage adjustment resistors, P-channel MOS driver transistor, N-channel MOS switching transistor for the synchronous switch, current limiter circuit, UVLO circuit and others. (See the block diagram above.) The series ICs compare, using the error amplifier, the voltage of the internal voltage reference source with the feedback voltage from the VOUT pin through split resistors, R1 and R2. Phase compensation is performed on the resulting error amplifier output, to input a signal to the PWM comparator to determine the turn-on time during PWM operation. The PWM comparator compares, in terms of voltage level, the signal from the error amplifier with the ramp wave from the ramp wave circuit, and delivers the resulting output to the buffer driver circuit to cause the Lx pin to output a switching duty cycle. This process is continuously performed to ensure stable output voltage. The current feedback circuit monitors the P-channel MOS driver transistor current for each switching operation, and modulates the error amplifier output signal to provide multiple feedback signals. This enables a stable feedback loop even when a low ESR capacitor such as a ceramic capacitor is used ensuring stable output voltage. <Reference Voltage Source> The reference voltage source provides the reference voltage to ensure stable output voltage of the DC/DC converter. <Ramp Wave Circuit> The ramp wave circuit determines switching frequency. The frequency is fixed internally and can be selected from 1.2MHz or 3.0MHz. Clock pulses generated in this circuit are used to produce ramp waveforms needed for PWM operation, and to synchronize all the internal circuits. <Error Amplifier> The error amplifier is designed to monitor output voltage. The amplifier compares the reference voltage with the feedback voltage divided by the internal split resistors, R1 and R2. When a voltage lower than the reference voltage is fed back, the output voltage of the error amplifier increases. The gain and frequency characteristics of the error amplifier output are fixed internally to deliver an optimized signal to the mixer. <Current Limit> The current limiter circuit of the XC9235/XC9236/XC9237 series monitors the current flowing through the P-channel MOS driver transistor connected to the Lx pin, and features a combination of the current limit mode and the operation suspension mode. When the driver current is greater than a specific level, the current limit function operates to turn off the pulses from the Lx pin at any given timing. When the driver transistor is turned off, the limiter circuit is then released from the current limit detection state. At the next pulse, the driver transistor is turned on. However, the transistor is immediately turned off in the case of an over current state. When the over current state is eliminated, the IC resumes its normal operation. The IC waits for the over current state to end by repeating the steps through . If an over current state continues for a few ms and the above three steps are repeatedly performed, the IC performs the function of latching the OFF state of the driver transistor, and goes into operation suspension mode. Once the IC is in suspension mode, operations can be resumed by either turning the IC off via the CE/MODE pin, or by restoring power to the VIN pin. The suspension mode does not mean a complete shutdown, but a state in which pulse output is suspended; therefore, the internal circuitry remains in operation. The current limit of the XC9235/XC9236/XC9237 series can be set at 1050mA at typical. Besides, care must be taken when laying out the PC Board, in order to prevent misoperation of the current limit mode. Depending on the state of the PC Board, latch time may become longer and latch operation may not work. In order to avoid the effect of noise, the board should be laid out so that input capacitors are placed as close to the IC as possible. Limit<#ms Limit>#ms ILIM ILx 0mA VOUT VSS Lx VCE Restart VIN 13/34 XC9235/XC9236/XC9237 Series OPERATIONAL DESCRIPTION (Continued) <Short-Circuit Protection> The short-circuit protection circuit monitors the internal R1 and R2 divider voltage from the VOUT pin (refer to FB point in the block diagram shown in the previous page). In case where output is accidentally shorted to the Ground and when the FB point voltage decreases less than half of the reference voltage (Vref) and a current more than the ILIM flows to the Pch MOS driver transistor, the short-circuit protection quickly operates to turn off and to latch the driver transistor. For the D/E/F/G series, it does not matter how much the current limit, once the FB voltage become less than the quarter of reference voltage (VREF), the short-circuit protection operates to latch the Pch MOS driver transistor. In latch mode, the operation can be resumed by either turning the IC off and on via the CE/MODE pin, or by restoring power supply to the VIN pin. When sharp load transient happens, a voltage drop at the VOUT is propagated to the FB point through CFB, as a result, short circuit protection may operate in the voltage higher than 1/2 VOUT voltage. <UVLO Circuit> When the VIN pin voltage becomes 1.4V or lower, the Pch MOS driver transistor output driver transistor is forced OFF to prevent false pulse output caused by unstable operation of the internal circuitry. When the VIN pin voltage becomes 1.8V or higher, switching operation takes place. By releasing the UVLO function, the IC performs the soft start function to initiate output startup operation. The soft start function operates even when the VIN pin voltage falls momentarily below the UVLO operating voltage. The UVLO circuit does not cause a complete shutdown of the IC, but causes pulse output to be suspended; therefore, the internal circuitry remains in operation. <PFM Switch Current> In PFM control operation, until coil current reaches to a specified level (IPFM), the IC keeps the Pch MOS driver transistor on. In this case, time that the Pch MOS driver transistor is kept on (TON) can be given by the following formula. tON= LxIPFM / (VINVOUT) IPFM < PFM Duty Limit > In PFM control operation, the PFM duty limit (DTYLIMIT_PFM) is set to 200% (TYP.). Therefore, under the condition that the duty increases (e.g. the condition that the step-down ratio is small), it's possible for Pch MOS driver transistor to be turned IPFM off even when coil current doesn't reach to IPFM. 14/34 XC9235/XC9236/XC9237 Series OPERATIONAL DESCRIPTION (Continued) CL High Speed Discharge XC9235B(C)(D)(E)(F)(G)/ XC9236B(C)(D)(E)(F)(G)/ XC9237B(C)(D)(E)(F)(G) series can quickly discharge the electric charge at the output capacitor (CL) when a low signal to the CE pin which enables a whole IC circuit put into OFF state, is inputted via the Nch MOS switch transistor located between the LX pin and the VSS pin. When the IC is disabled, electric charge at the output capacitor (CL) is quickly discharged so that it may avoid application malfunction. Discharge time of the output capacitor (CL) is set by the CL auto-discharge resistance (R) and the output capacitor (CL). By setting time constant of a CL auto-discharge resistance value [R] and an output capacitor value (CL) as (=C x R), discharge time of the output voltage after discharge via the N channel transistor is calculated by the following formulas. -t/ V = VOUT(E) x e or t=Ln (VOUT(E) / V) V : Output voltage after discharge VOUT(E) : Output voltage t: Discharge time : C x R C= Capacitance of Output capacitor (CL) R= CL auto-discharge resistance Output Voltage Dischage Characteristics Rdischg = 300 TYP 100 90 CL=10uF 80 CL=20uF 70 CL=50uF 60 50 40 30 20 10 0 0 10 20 30 40 50 60 70 80 90 100 Discharge Time t (ms) 15/34 XC9235/XC9236/XC9237 Series OPERATIONAL DESCRIPTION (Continued) <CE/MODE Pin Function> The operation of the XC9235/XC9236/XC9237 series will enter into the shut down mode when a low level signal is input to the CE/MODE pin. During the shutdown mode, the current consumption of the IC becomes 0A (TYP.), with a state of high impedance at the Lx pin and VOUT pin. The IC starts its operation by inputting a high level signal to the CE/MODE pin. The input to the CE/MODE pin is a CMOS input and the sink current is 0A (TYP.). XC9235/XC9236 series - Examples of how to use CE/MODE pin (A) SWCE STATUS ON Stand-by OFF Operation (B) SWCE STATUS ON Operation OFF Stand-by (A) (B) XC9237 series - Examples of how to use CE/MODE pin (A) SWCE SWPWM/PFM STATUS ON * PWM/PFM Automatic Switching Control OFF ON PWM Control OFF OFF Stand-by SWCE SWPWM/PFM STATUS (B) ON * Stand-by OFF ON PWM Control OFF OFF PWM/PFM Automatic Switching Control (A) Intermediate voltage can be generated by RM1 and RM2. Please set the value of each R1, R2, RM1, RM2 from few hundreds k to few hundreds M. For switches, CPU open-drain I/O port and transistor can be used. 16/34 (B) XC9235/XC9236/XC9237 Series OPERATIONAL DESCRIPTION (Continued) Soft Start Soft start time is available in two options via product selection. The A,C,D,and E types of XC9235/XC9236/XC9237 se<External Components> XC9237A18D tSS VCEH 0V 90% of setting voltage VOUT 0V FUNCTION CHART CE/MODE VOLTAGE LEVEL OPERATIONAL STATES XC9235 XC9236 XC9237 H Level (*1) Synchronous PWM Fixed Control Synchronous PWM/PFM Automatic Switching M Level (*2) Synchronous PWM/PFM Automatic Switching Synchronous PWM Fixed Control L Level (*3) Stand-by Stand-by Stand-by Note on CE/MODE pin voltage level range (*1) H level: 0.65V < VCE/MODE < 6.0V (for XC9235/XC9236) H level: VIN - 0.25V < VCE/MODE < VIN (for XC9237) (*2) M level: 0.65V < VCE/MODE < VIN - 1.0V (for XC9237) (*3) L level: 0V < VCE/MODE < 0.25V 17/34 XC9235/XC9236/XC9237 Series NOTE ON USE 1. For temporary, transitional voltage drop or voltage rising phenomenon, the IC is liable to malfunction should the ratings be exceeded. 2. The XC9235/XC9236/XC9237 series is designed for use with ceramic output capacitors. If, however, the potential difference is too large between the input voltage and the output voltage, a ceramic capacitor may fail to absorb the resulting high switching energy and oscillation could occur on the output. If the input-output potential difference is large, connect an electrolytic capacitor in parallel to compensate for insufficient capacitance. 3. Spike noise and ripple voltage arise in a switching regulator as with a DC/DC converter. These are greatly influenced by external component selection, such as the coil inductance, capacitance values, and board layout of external components. Once the design has been completed, verification with actual components should be done. 4. Depending on the input-output voltage differential, or load current, some pulses may be skipped, and the ripple voltage may increase. 5. When the difference between VIN and VOUT is large in PWM control, very narrow pulses will be outputted, and there is the possibility that some cycles may be skipped completely. 6. When the difference between VIN and VOUT is small, and the load current is heavy, very wide pulses will be outputted and there is the possibility that some cycles may be skipped completely. 7. With the IC, the peak current of the coil is controlled by the current limit circuit. Since the peak current increases when dropout voltage or load current is high, current limit starts operation, and this can lead to instability. When peak current becomes high, please adjust the coil inductance value and fully check the circuit operation. In addition, please calculate the peak current according to the following formula: Ipk = (VIN - VOUT) x OnDuty / (2 x L x fOSC) + IOUT L: Coil Inductance Value fOSC: Oscillation Frequency 8. When the peak current which exceeds limit current flows within the specified time, the built-in Pch MOS driver transistor turns off. During the time until it detects limit current and before the built-in transistor can be turned off, the current for limit current flows; therefore, care must be taken when selecting the rating for the external components such as a coil. 9. When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance. 10. Care must be taken when laying out the PC Board, in order to prevent misoperation of the current limit mode. Depending on the state of the PC Board, latch time may become longer and latch operation may not work. In order to avoid the effect of noise, the board should be laid out so that input capacitors are placed as close to the IC as possible. 11. Use of the IC at voltages below the recommended voltage range may lead to instability. 12. This IC should be used within the stated absolute maximum ratings in order to prevent damage to the device. 13. When the IC is used in high temperature, output voltage may increase up to input voltage level at no load because of the leak current of the driver transistor. 14. The current limit is set to 1350mA (MAX.) at typical. However, the current of 1350mA or more may flow. In case that the current limit functions while the VOUT pin is shorted to the GND pin, when Pch MOS driver transistor is ON, the potential difference for input voltage will occur at both ends of a coil. For this, the time rate of coil current becomes large. By contrast, when Nch MOS driver transistor is ON, there is almost no potential difference at both ends of the coil since the VOUT pin is shorted to the GND pin. Consequently, the time rate of coil current becomes quite small. According to the repetition of this operation, and the delay time of the circuit, coil current will be converged on a certain current value, exceeding the amount of current, which is supposed to be limited originally. Even in this case, however, after the over current state continues for several ms, the circuit will be latched. A coil should be used within the stated absolute maximum rating in order to prevent damage to the device. Current flows into Pch MOS driver transistor to reach the current limit (ILIM). The current of ILIM or more flows since the delay time of the circuit occurs during from the detection of the current limit to OFF of Pch MOS driver transistor. Because of no potential difference at both ends of the coil, the time rate of coil current becomes quite small. Lx oscillates very narrow pulses by the current limit for several ms. The circuit is latched, stopping its operation. 18/34 XC9235/XC9236/XC9237 Series NOTE ON USE (Continued) 15. In order to stabilize VIN's voltage level and oscillation frequency, we recommend that a by-pass capacitor (CIN) be connected as close as possible to the VIN & VSS pins. 16. High step-down ratio and very light load may lead an intermittent oscillation. 17. During PWM / PFM automatic switching mode, operating may become unstable at transition to continuous mode. Please verify with actual parts. 18. Please note the inductance value of the coil. The IC may enter unstable operation if the combination of ambient temperature, setting voltage, oscillation frequency, and L value are not adequate. In the operation range close to the maximum duty cycle, The IC may happen to enter unstable output voltage operation even if using the L values listed below. <External Components> The Range of L Value fOSC VOUT L Value 3.0MHz 0.8VVOUT<4.0V 1.0H2.2H VOUT2.5V 3.3H6.8H 2.5VVOUT 4.7H6.8H 1.2MHz *When a coil less value of 4.7H is used at fOSC=1.2MHz or when a coil less value of 1.5H is used at fOSC=3.0MHz, peak coil current more easily reach the current limit ILMI. In this case, it may happen that the IC can not provide 600mA output current. 19. It may happen to enter unstable operation when the IC goes into continuous operation mode under the condition of large input-output voltage difference. Care must be taken with the actual design unit. <External Components> 20. Torex places an importance on improving our products and their reliability. We request that users incorporate fail-safe designs and post-aging protection treatment when using Torex products in their systems. 19/34 XC9235/XC9236/XC9237 Series NOTE ON USE (Continued) 21. Instructions of pattern layouts (1) In order to stabilize VIN voltage level, we recommend that a by-pass capacitor (CIN) be connected as close as possible to the VIN & VSS pins. (2) Please mount each external component as close to the IC as possible. (3) Wire external components as close to the IC as possible and use thick, short connecting traces to reduce the circuit impedance. (4) Make sure that the PCB GND traces are as thick as possible, as variations in ground potential caused by high ground currents at the time of switching may result in instability of the IC. (5) This series' internal driver transistors bring on heat because of the output current and ON resistance of driver transistors. 22. NOTE ON MOUNTING (WLP-5-03) (1) Mount pad design should be optimized for user's conditions. (2) Sn-AG-Cu is used for the package terminals. If eutectic solder is used, mounting reliability is decreased. Please do not use eutectic solder paste. (3) When underfill agent is used to increase interfacial bonding strength, please take enough evaluation for selection. Some underfill materials and applied conditions may decrease bonding reliability. (4) The IC has exposed surface of silicon material in the top marking face and sides so that it is weak against mechanical damages. Please take care of handling to avoid cracks and breaks. (5) The IC has exposed surface of silicon material in the top marking face and sides. Please use the IC with keeping the circuit open (avoiding short-circuit from the out). (6) Semi-transparent resin is coated on the circuit face of the package. Please be noted that the usage under strong lights may affects device performance. 20/34 XC9235/XC9236/XC9237 Series TEST CIRCUITS < Circuit No.1 > A/B/C/E/G series D/F series Wave Form Measure Point A VIN Wave Form Measure Point L L A Lx VIN IOUT Lx Cfb CIN CE/MODE VSS CIN VOUT CL V R1 CL CE/MODE RL VSS FB V RL R2 External Components L External Components L CIN CL R1 R2 Cfb : 1.5uH(NR3015) 3.0MHz 4.7uH(NR4018) 1.2MHz CIN : 4.7F(ceramic) CL :10F(ceramic) < Circuit No.2 > : 1.5H(NR4018) 3.0MHz : 4.7H (NR3015) 1.2MHz : 4.7F : 10F : 150k : 300k : 120pF VOUT=VFBx(R1+R2)/R2 < Circuit No.3 > Wave Form Measure Point A 1uF VIN CE/MODE VSS Lx VIN VOUT (FB) CE/MODE VSS 1uF Lx VOUT (FB) Rpulldown 200 < Circuit No.5 > < Circuit No.4 > VIN Lx VIN Lx A ICEH 1uF CE/MODE VSS VOUT (FB) V 100mA A 1uF CE/MODE VSS VOUT (FB) ICEL ON resistance = (VIN-VLx)/100mA < Circuit No.7 > < Circuit No.6 > Wave Form Measure Point Wave Form Measure Point VIN 1uF CE/MODE VSS VIN Lx VOUT (FB) V ILIM 1uF CE/MODE VSS Lx VOUT (FB) Ilat Rpulldown 1 < Circuit No.8 > ILx VIN 1uF CE/MODE VSS Lx VOUT (FB) A < Circuit No.9 > A CIN VIN CE/MODE VSS Lx VOUT (FB) 21/34 XC9235/XC9236/XC9237 Series TYPICAL PERFORMANCE CHARACTERISTICS (1) Efficiency vs. Output Current XC9237A18C XC9237A18D L=1.5H (NR3015), CIN=4.7F, CL=10F L=4.7H (NR40Ambient Temperature: Ta () PWM/PFM Automatic Sw itching Control 100 100 90 80 80 VIN= 4.2V 70 60 PWM Control VIN= 4.2V 3.6V 2.4V 3.6V 50 Efficiency: EFFI (%) Efficency:EFFI(%) Efficiency: EFFI (%) Efficency:EFFI(%) PWM/PFM Automatic Sw itching Control 90 2.4V 40 30 70 VIN= 4.2V 60 3.6V 50 PWM Control VIN= 4.2V 3.6V 2.4V 2.4V 40 30 20 20 10 10 0 0 0.1 1 Output Current: 10 IOUT (mA) 100 0.1 1000 1Output Current: 10IOUT (mA) 100 1000 Output Current:IOUT(mA) Output Current:IOUT(mA) (2) Output Voltage vs. Output Current Soft-Start Time, XC9237A18D L=1.5H (NR3015), CIN=4.7F, CL=10F Setting 2.1 2.1 2.0 2.0 Output Voltage:Vout(V) Output Voltage:Vout(V) Output Voltage: VOUT (V) XC923 PWM/PFM Automatic Sw itching Control VIN4.2V,3.6V,2.4V 1.9 1.8 1.7 PWM Control 1.6 PWM/PFM Automatic Sw itching Control VIN4.2V,3.6V,2.4V 1.9 1.8 1.7 PWM Control 1.6 1.5 1.5 0.1 1 10 100 1000 0.1 Output Current: IOUT (mA) 1 10 100 1000 Output Current: IOUT (mA) Output Current:IOUT(mA) Output Current:IOUT(mA) (3) Ripple Voltage vs. Output Current XC9237A18D L=1.5H (NR3015), CIN=4.7F, CL=10F XC9237A18C L=4.7H (NR4018), CIN=4.7F, CL=10F 100 100 80 60 PWM/PFM Automatic Sw itching Control VIN4.2V 3.6V 2.4V PWM Control VIN4.2V,3.6V,2.4V 40 Ripple Voltage:Vr(mV) Ripple Voltage: Vr (mV) Ripple Voltage:Vr(mV) 80 20 PWM/PFM Automatic PWM Control VIN4.2V,3.6V,2.4V Sw itching Control VIN4.2V 3.6V 2.4V 40 20 0 0 0.1 1 10 100 Output IOUT (mA) OutputCurrent: Current:IOUT(mA) 22/34 60 1000 0.1 1 10 100 Output IOUT Supply OutputCurrent: Current:IOUT(mA) 1000 XC9235/XC9236/XC9237 Series TYPICAL PERFORMANCE CHARACTERISTICS (Continued) (4) Oscillation Frequency vs. Ambient Temperature XC9237A18D L=1.5H (NR3015), CIN=4.7F, CL=10F XC9237A18C L=4.7H (NR4018), CIN=4.7F, CL=10F 3.5 Oscillation Frequency Frequency: FOSC (MHz) Oscillation : FOSC(MHz) Oscillation Frequency: (MHz) Oscillation FrequencyFOSC : FOSC(MHz) 1.5 1.4 1.3 VIN=3.6V 1.2 1.1 1.0 0.9 0.8 3.4 3.3 3.2 VIN=3.6V 3.1 3.0 2.9 2.8 2.7 2.6 2.5 -50 -25 0 25 50 75 100 -50 -25 Ambient Ta() ( ) AmbientTemperature: Temperature: Ta 0 25 50 75 100 Ambient ( ) Ambient Temperature: Temperature: TaTa () (5) Supply Current vs. Ambient Temperature XC9237A18D 40 40 35 35 30 VIN=6.0V 25 20 SupplyCurrent: CurrentIDD : IDD (A) Supply (A) Supply Current: (A) Supply CurrentIDD : IDD (A) XC9237A18C VIN=4.0V VIN=2.0V 15 10 5 0 -50 30 VIN=6.0V VIN=4.0V VIN=2.0V 25 20 15 10 5 -25 0 25 50 75 0 -50 100 -25 Ambient Temperature: Temperature: TaTa () Ambient ( ) 0 25 50 75 100 Ambient Temperature: Temperature: TaTa () Ambient ( ) (6) Output Voltage vs. Ambient Temperature (7) UVLO Voltage vs. Ambient Temperature XC9237A18D XC9237A18D 2.1 1.8 2.0 1.5 1.9 UVLOVoltage Voltage:: UVLO UVLO UVLO(V) (V) Output VOUT(V)(V) OutputVoltage Voltage::VOUT CE=VIN VIN=3.6V 1.8 1.7 1.6 1.5 1.2 0.9 0.6 0.3 0.0 -50 -25 0 25 50 Ambient ( ) Ambient Temperature: Temperature: TaTa () 75 100 -50 -25 0 25 50 75 100 Ambient ( ) Ambient Temperature: Temperature: TaTa () 23/34 XC9235/XC9236/XC9237 Series TYPICAL PERFORMANCE CHARACTERISTICS (Continued) (8) CE "H" Voltage vs. Ambient Temperature (9) CE "L" Voltage vs. Ambient Temperature XC9237A18D 1.0 1.0 0.9 0.9 0.8 0.8 0.7 CE"L" "L" Voltage Voltage: VCEL (V)(V) CE : VCEL CE "H" Voltage: VCEH (V) CE "H" Voltage : VCEH (V) XC9237A18D VIN=5.0V 0.6 0.5 0.4 0.3 VIN=2.4V 0.2 VIN=3.6V 0.1 VIN=5.0V 0.7 0.6 0.5 0.4 VIN=3.6V 0.3 VIN=2.4V 0.2 0.1 0.0 0.0 -50 -25 0 25 50 75 100 -50 -25 Ambient Temperature: Ta ( ) Ambient TempOutput Current: IOUT (mA) 0 25 50 75 100 Ambient Temperature:TaTa ( ) Ambient Temperature: () (10) Soft Start Time vs. Ambient Temperature XC9237A18D L=1.5H (NR3015), CIN=4.7F, CL=10F 5 5 4 4 SoftStart Start Time Time: TSS (ms) Soft : TSS (ms) Soft TimeTSS : TSS (ms) Soft Start Start Time: (ms) XC9237A18C L=4.7H (NR4018), CIN=4.7F, CL=10F 3 2 VIN=3.6V 1 0 -50 -25 0 25 50 75 100 AmbiRipple Voltage: Vr (mV) Ambient Temperature: Ta ( ) Lx Resistance: RLxH, RLxL () () LxSW SWON ON Resistance:RLxH,RLxL XC9237A18D 1.0 0.9 0.8 Nch on Resistance 0.6 0.5 0.4 0.3 Pch on Resistance 0.2 0.1 0.0 0 1 2 3 4 Input Voltage: VIN (V)<External Components> Input Voltage : VIN (V) 24/34 2 VIN=3.6V 1 0 -50 -25 0 25 50 Ambient Temperature: () Ambient Temperature:TaTa ( ) (11) "Pch / Nch" Driver on Resistance vs. Input Voltage 0.7 3 5 6 75 100 XC9235/XC9236/XC9237 Series TYPICAL PERFORMANCE CHARACTERISTICS (Continued) (12) XC9235B/36B/37B Rise Wave Form XC9237B12C L=4.7H (NR4018), CIN=4.7F, CL=10F XC9237B33D L=1.5H (NR3015), CIN=4.7F, CL=10F VIN=5.0V VIN=5.0V IOUT=1.0mA IOUT=1.0mA VOUT1.0V/div VOUT0.5V/div CE0.0V1.0V CE0.0V1.0V 100s/div 100s/div (13) XC9235B/36B/37B Soft-Start Time vs. Ambient Temperature XC9237B12C XC9237B33D L=1.5H(NR3015), CIN=4.7F, CL=10F 500 500 400 400 Soft Start Time :TSS (s) Soft Start Time :TSS (s) L=4.7H(NR4018), CIN=4.7F, CL=10F 300 200 VIN=5.0V IOUT=1.0mA 100 300 200 VIN=5.0V IOUT=1.0mA 100 0 0 -50 -25 0 25 50 75 100 -50 0 25 50 75 100 Ambient Temperature: Ta() Ambient Temperature: Ta() (14) XC9235B/36B/37B -25 CL Discharge Resistance vs. Ambient Temperature XC9237B33D 600 CL Discharge Resistance: () VIN=6.0V 500 VIN=4.0V VIN=2.0V 400 300 200 100 -50 -25 0 25 50 75 100 Ambient Temperature: Ta () 25/34 XC9235/XC9236/XC9237 Series TYPICAL PERFORMANCE CHARACTERISTICS (Continued) (15) Load Transient Response XC9237A18C L=4.7H (NR4018), CIN=4.7F (ceramic), CL=10F (ceramic), Topr=25 VIN=3.6V, VCE=VIN (PWM/PFM Automatic Switching Control) IOUT=1mA 100mA IOUT=1mA 300mA 1ch: IOUT 1ch: IOUT 2ch 2ch VOUT: 50mV/div VOUT: 50mV/div 50s/div 50s/div IOUT=100mA 1mA IOUT=300mA 1mA 1ch: IOUT 1ch: IOUT 2ch 2ch VOUT: 50mV/div VOUT: 50mV/div 200s/div 26/34 200s/div XC9235/XC9236/XC9237 Series TYPICAL PERFORMANCE CHARACTERISTICS (Continued) (15) Load Transient Response (Continued) XC9237A18C L=4.7H (NR4018), CIN=4.7F (ceramic), CL=10F (ceramic), Topr=25 VIN=3.6V, VCE=1.8V (PWM Control) IOUT=1mA 100mA IOUT=1mA 300mA 1ch: IOUT 1ch: IOUT 2ch 2ch VOUT: 50mV/div VOUT: 50mV/div 50s/div 50s/div IOUT=100mA 1mA IOUT=300mA 1mA 1ch: IOUT 1ch: IOUT 2ch 2ch VOUT: 50mV/div VOUT: 50mV/div 200s/div 200s/div 27/34 XC9235/XC9236/XC9237 Series TYPICAL PERFORMANCE CHARACTERISTICS (Continued) (15) Load Transient Response (Continued) XC9237A18D L=1.5H (NR3015), CIN=4.7F (ceramic), CL=10F (ceramic), Topr=25 VIN=3.6V, VCE=VIN (PWM/PFM Automatic Switching Control) IOUT=1mA 100mA IOUT=1mA 300mA 1ch: IOUT 1ch: IOUT 2ch 2ch VOUT: 50mV/div VOUT: 50mV/div 50s/div 50s/div IOUT=100mA 1mA IOUT=300mA 1mA 1ch: IOUT 1ch: IOUT 2ch 2ch VOUT: 50mV/div VOUT: 50mV/div 200s/div 28/34 200s/div XC9235/XC9236/XC9237 Series TYPICAL PERFORMANCE CHARACTERISTICS (Continued) (15) Load Transient Response (Continued) XC9237A18D L=1.5H (NR3015), CIN=4.7F (ceramic), CL=10F (ceramic), Topr=25 VIN=3.6V, VCE=1.8V (PWM Control) IOUT=1mA 100mA IOUT=1mA 300mA 1ch: IOUT 1ch: IOUT 2ch 2ch VOUT: 50mV/div VOUT: 50mV/div 50s/div 50s/div IOUT=100mA 1mA IOUT=300mA 1mA 1ch: IOUT 1ch: IOUT 2ch 2ch VOUT: 50mV/div VOUT: 50mV/div 200s/div 200s/div 29/34 XC9235/XC9236/XC9237 Series PACKAGING INFORMATION SOT-25 USP-6C USP-6C Reference Pattern Layout USP-6C Reference Metal Mask Design 2.4 0.45 0.45 1 6 2 5 3 4 0.05 0.05 1.0 30/34 XC9235/XC9236/XC9237 Series PACKAGING INFORMATION (Continued) USP-6EL * A part of the pin may appear from the side of the package because of it's structure, but reliability of the package and strength will not be changed below the standard. USP-6EL Reference Pattern Layout USP-6EL Reference Metal Mask Design 1.4 1.5 0.3 0.35 2.2 0.9 2.25 0.3 0.375 1.1 0.3 0.375 0.5 0.55 0.55 0.55 0.55 31/34 XC9235/XC9236/XC9237 Series PACKAGING INFORMATION (Continued) WLP-5-03 1.060.04 1pin INDENT (0.3) 1 4 5 2 3 (0.5) 32/34 XC9235/XC9236/XC9237 Series MARKING RULE SOT-25 represent product series PRODUCT XC9235 SERIES A B C D E F G SOT-25 (TOP VIEW) USP-6C/USP-6EL (TOP VIEW) WLP-5-03 2 1 4 5 3 WLP-5-03 (TOP VIEW) XC9237 5 D L L 5 7 D 6 E M M 6 B E represents integer number of output voltage and oscillation frequency A/B/C/F Series OUTPUT MARK VOLTAGE (V) fOSC=1.2MHz fOSC=3.0MHz 0.X 1.X 2.X 3.X 4.X USP-6C/USP-6EL 4 C K K 4 2 C XC9236 E/G/D Series OUTPUT VOLTAGE (V) 0.X 1.X 2.X 3.X 4.X A B C D E F H K L M MARK fOSC=1.2MlHz fOSC=3.0MlHz N P R S T U V X Y Z represents decimal point of output voltage VOUT (V) MARK VOUT (V) X.00 X.10 X.20 X.30 X.40 X.50 X.60 X.70 X.80 X.90 0 1 2 3 4 5 6 7 8 9 X.05 X.15 X.25 X.35 X.45 X.55 X.65 X.75 X.85 X.95 MARK A B C D E F H K L M represents production lot number Order of 0109, 0A0Z, 119Z, A1A9, AAAZ, B1ZZ. (G, I, J, O, Q, W excluded) *No character inversion used. 33/34 XC9235/XC9236/XC9237 Series 1. The products and product specifications contained herein are subject to change without notice to improve performance characteristics. Consult us, or our representatives before use, to confirm that the information in this datasheet is up to date. 2. We assume no responsibility for any infringement of patents, patent rights, or other rights arising from the use of any information and circuitry in this datasheet. 3. Please ensure suitable shipping controls (including fail-safe designs and aging protection) are in force for equipment employing products listed in this datasheet. 4. The products in this datasheet are not developed, designed, or approved for use with such equipment whose failure of malfunction can be reasonably expected to directly endanger the life of, or cause significant injury to, the user. (e.g. Atomic energy; aerospace; transport; combustion and associated safety equipment thereof.) 5. Please use the products listed in this datasheet within the specified ranges. Should you wish to use the products under conditions exceeding the specifications, please consult us or our representatives. 6. We assume no responsibility for damage or loss due to abnormal use. 7. All rights reserved. No part of this datasheet may be copied or reproduced without the prior permission of TOREX SEMICONDUCTOR LTD. 34/34