MAX8645X/MAX8645Y 19-3978 Rev 4 6/08 1x/1.5x/2x White LED Charge Pumps with Two LDOs in 4mm x 4mm TQFN General Description Features The MAX8645X/MAX8645Y charge pumps drive up to Power Up to Eight LEDs eight white LEDs with regulated constant current for uni- Up to 30mA/LED Drive for Backlight form intensity. The main group of LEDs (M1M6) can be driven up to 30mA per LED for backlighting. The flash Up to 400mA Total Drive for Flash group of LEDs (F1 and F2) is independently controlled Two Internal Low-Noise 200mA LDOs and can be driven up to 200mA per LED (or 400mA total). Two 200mA LDOs are on-board to provide power for 94% Max/85% Avg Efficiency (P /P ) over Li+ LED BATT camera functions. The LDOs output voltages are pin pro- Battery Discharge grammable to meet different camera-module require- ments. The MAX8645X and MAX8645Y differ only in LDO 0.2% Typical LED Current Matching output voltages. By utilizing adaptive 1x/1.5x/2x charge- pump modes and very-low-dropout current regulators, Adaptive 1x/1.5x/2x Mode Switchover the MAX8645X/MAX8645Y achieve high efficiency over Single-Wire, Serial-Pulse Interface for Brightness the full 1-cell lithium-battery voltage range. The 1MHz fixed-frequency switching allows for tiny external compo- Control (32 Steps) nents, and the regulation scheme is optimized to ensure Thermal T Derating Function A low EMI and low input ripple. The MAX8645X/MAX8645Y are available in a 28-pin TQFN, Low Input Ripple and EMI 4mm x 4mm (0.8mm max height) lead-free package. 2.7V to 5.5V Supply Voltage Range Soft-Start, Overvoltage, and Thermal-Shutdown Applications Protection Camera Phones and Smartphones 28-Pin TQFN, 4mm x 4mm Package Backlighting and Flash PDAs, Digital Cameras, and Camcorders Typical Operating Circuit Ordering Information PART TEMP RANGE PIN-PACKAGE 1F 1F 28 TQFN-EP INPUT OUTPUT MAX8645XETI+ -40C to +85C C1P C1N C2P C2N UP TO 580mA 2.7V TO 5.5V 4mm x 4mm PIN OUT MAIN FLASH 10F IN 28 TQFN-EP MAX8645YETI+ -40C to +85C 10F MAX8645X 4mm x 4mm GND MAX8645Y M1 PGND EP = Exposed pad. M2 M3 +Denotes a lead-free package. M4 ENM1 MAIN ON/OFF M5 AND DIMMING ENM2 M6 F1 ENF FLASH ON/OFF F2 LDO1 DUAL-LDO ON/OFF ENLDO CAMERA LDO2 MODULE DUAL-LDO P1 1F 1F VOLTAGE SELECTION P2 SETM SETF REF Pin Configuration appears at end of data sheet. 0.01F Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim s website at www.maxim-ic.com. EVALUATION KIT AVAILABLE1x/1.5x/2x White LED Charge Pumps with Two LDOs in 4mm x 4mm TQFN ABSOLUTE MAXIMUM RATINGS PIN, IN, OUT, REFBP to GND................................-0.3V to +6.0V OUT, LDO1, LDO2 Short Circuit to GND ...................Continuous SETF, SETM, ENLDO, ENM1, ENM2, ENF, Continuous Power Dissipation (T = +70C) A P1, P2, LDO1, LDO2 to GND....................-0.3V to (V + 0.3V) 28-Pin TQFN 4mm x 4mm IN M1, M2, M3, M4, M5, M6, F1, (derate 20.8mW/C above +70C).............................1666mW F2 to GND.............................................-0.3V to (V + 0.3V) Operating Temperature Range ...........................-40C to +85C OUT C1N, C2N to GND ......................................... -0.3V to (V + 1V) Junction Temperature......................................................+150C IN C1P, C2P Storage Temperature Range .............................-65C to +150C to GND........ -0.3V to the greater of (V + 1V) or (V + 1V) Lead Temperature (soldering, 10s) .................................+300C OUT IN PGND to GND .......................................................-0.3V to +0.3V Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = 3.6V, V = V = 0V, ENM1 = ENM2 = ENF = IN, R = R = 6.8k, P1 = P2 = unconnected, C = 0.01F, IN GND PGND SETM SETF REF T = -40C to +85C, unless otherwise noted. Typical values are at T = +25C.) (Note 1) A A PARAMETER CONDITIONS MIN TYP MAX UNITS IN Operating Voltage 2.7 5.5 V Undervoltage-Lockout Threshold V rising or falling 2.25 2.45 2.60 V IN Undervoltage-Lockout Hysteresis 130 mV 1MHz switching, no load, 1.5x or 2x mode 4.0 5.5 mA 1x mode 10% setting, ENF = GND, V = V , ENLDO IN 0.4 I = I = 0A Supply Current LDO1 LDO2 ENM1 = ENM2 = ENF = GND, V = V , ENLDO IN 110 A I = I = 0A LDO1 LDO2 T = +25C 0.01 5 A Shutdown Supply Current ENM1 = ENM2 = ENF = ENLDO = GND A T = +85C 0.1 A EN High Voltage V = 2.7V to 5.5V 1.4 V IN EN Low Voltage V = 2.7V to 5.5V 0.4 V IN T = +25C 0.01 1 A EN Input Current V = 0V or 5.5V A EN T = +85C 0.1 A ENM or ENF Low Shutdown See Figure 1 2.5 ms Delay t SHDN ENM or ENF t See Figure 1 0.5 250.0 s LO ENM or ENF t See Figure 1 0.5 s HI Initial ENM or ENF t Only required for first ENM or ENF pulse see Figure 1 200 s HI P1, P2 Shutdown Input Current 1A P1, P2 Input Impedance 150 k Thermal-Shutdown Threshold Temperature rising +160 C Thermal-Shutdown Hysteresis 20 C CHARGE PUMP Overvoltage-Protection Threshold V rising 5 V OUT Soft-Start Time 2ms 2 MAX8645X/MAX8645Y