MAX1573 19-2847 Rev 2 8/05 White LED 1x/1.5x Charge Pump in UCSP and Thin QFN General Description Features The MAX1573 fractional charge pump drives up to four Proprietary Adaptive 1x/1.5x Modes white LEDs with regulated constant current for uniform High Efficiency (P /P ), Up to 92% LEDs BATT intensity. By utilizing proprietary adaptive 1x/1.5x 0.2% LED Current Matching modes and ultra-low-dropout current regulators, it maintains the highest possible efficiency over the full 28mA/LED Drive Capability 1-cell Li+ battery input voltage range. The 1MHz fixed- Low Input Ripple and EMI frequency switching allows for tiny external compo- nents and the regulation scheme is optimized to ensure Eliminates Ballast Resistors low EMI and low input ripple. Logic or PWM Dimming Control An external resistor sets the full-scale LED current, while Low 0.1A Shutdown Current two digital inputs control on/off and select amongst three 2.7V to 5.5V Input Voltage Range levels of brightness. A pulse-width modulation (PWM) signal can also be used to modulate LED brightness, Soft-Start Limits Inrush Current requiring no additional components. Output Overvoltage Protection The MAX1573 is available in the tiny chip-scale UCSP Thermal Shutdown Protection (4 x 4 grid) and 16-pin thin QFN packages. No External Schottky Diode Required Tiny UCSP (2.1mm x 2.1mm x 0.6mm) and Thin QFN (4mm x 4mm) Packages Applications Cell Phones, Smart Phones Ordering Information PDAs, Digital Cameras, Camcorders PART TEMP RANGE PIN-PACKAGE MP3 Players MAX1573EBE-T -40C to +85C 14 UCSP (4 x 4) MAX1573ETE -40C to +85C 16 Thin QFN Other Handhelds with Color Displays MAX1573ETE+ -40C to +85C 16 Thin QFN + Denotes lead-free package. Typical Operating Circuit Pin Configurations TOP VIEW 1F 1F 12 11 10 9 V C1N C1P C2N C2P OUT V CIN 13 8 LED1 IN UP TO 4 LEDS 2.7V TO 5.5V IN OUT 1F 1F IN 14 7 LED2 MAX1573 ON/OFF MAX1573 C2N 15 6 SET LED1 EN1 AND DIMMING EN2 LED2 C1P EN2 CONTROL 16 5 LED3 12 3 4 LED4 SET GND R SET THIN QFN 4mm 4mm A SIGN WILL REPLACE THE FIRST PIN INDICATOR ON LEAD-FREE PACKAGES. Pin Configurations continued at end of data sheet. UCSP is a trademark of Maxim Integrated Products, Inc. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. C2P N.C. OUT GND EN1 LED3 N.C. LED4White LED 1x/1.5x Charge Pump in UCSP and Thin QFN ABSOLUTE MAXIMUM RATINGS IN, OUT, EN1, EN2 to GND...................................-0.3V to +6.0V Continuous Power Dissipation (T = +70C) A SET, LED1, LED2, LED3, LED4 to GND ......-0.3V to (V + 0.3V) 14-Bump UCSP (derate 7.36mW/C above +70C) ....589mW IN C1N, C2N to GND ..........................................-0.3V to (V + 1V) 16-Pin Thin QFN (derate 16.9mW/C above +70C) .1349mW IN C1P, C2P to GND............................................-0.3V to greater of Operating Temperature Range ...........................-40C to +85C .............................................................(V + 1V) or (V + 1V) Junction Temperature......................................................+150C OUT IN OUT Short Circuit to GND ..........................................Continuous Storage Temperature Range .............................-65C to +150C 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 = V = V = 3.6V, C = C1 = C2 = C = 1F, T = -40C to +85C. Typical values are at T = +25C, unless otherwise IN EN1 EN2 IN OUT A A noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS IN Operating Voltage 2.7 5.5 V Undervoltage Lockout Threshold V rising or falling, 35mV hysteresis 2.25 2.45 2.60 V IN Supply Current Switching, no load, I = 130A 2 4 mA SET Shutdown Supply Current EN1 = EN2 = OUT = GND, T = +25C 0.1 10 A A Soft-Start Completion Time 2.1 ms SET Bias Voltage 0.570 0.6 0.630 V SET Leakage in Shutdown EN1 = EN2 = GND, T = +25C 0.01 1A A SET Current Range 40 130 A EN1 = EN2 = IN 190 219 245 SET to LED Current Ratio (I /I)I = 60A EN1 = IN, EN2 = GND 58 66 74 A/A LED SET SET EN1 = GND, EN2 = IN 19.5 22 25.0 LED Current Accuracy E N 1 = EN 2 = IN, R = 4.64k, T = 0C to +85 C 0.6 % S E T A LED Current Matching I = 130A, T = 0C to +85C (Note 2) 0.2 % SET A Maximum LED Sink Current I = 130A, EN1 = EN2 = IN 25.9 28 mA SET LED Dropout Voltage I = 87A (Note 3) 40 80 mV SET LED Minimum Regulation Voltage (1.5x Mode) EN1 = EN2 = IN, I = 87A 100 150 200 mV SET LED Leakage in Shutdown EN1 = EN2 = GND, V = 5.5V, T = +25C 0.01 1A LED A Maximum OUT Current V 3.4V, V 3.9V, EN1 = EN2 = IN 120 mA IN OUT 1x mode (1 x V - V ) / I 1.5 IN OUT OUT Open-Loop OUT Resistance 1.5x mode (1.5 x V - V ) / I 10 IN OUT OUT Switching Frequency 1 MHz EN1, EN2 Logic High Voltage V = 2.7V to 5.5V 1.6 V IN EN1, EN2 Logic Low Voltage V = 2.7V to 5.5V 0.4 V IN EN1, EN2 Input Current V = GND or 5.5V, T = +25C 0.01 1A EN A Thermal-Shutdown Threshold 20C hysteresis 160 C Note 1: Specifications to -40C are guaranteed by design and not production tested. Note 2: LED current matching is defined as: (I - I ) / I . LED AVG AVG Note 3: Dropout voltage is defined as the LED to GND voltage at which the LED current drops 10% from the value at V = 200mV. LED 2 MAX1573