MAX1570 Series

White LED Current Regulator with 1x/1.5x High-Efficiency Charge Pump

Manufacturer: Analog Devices Inc./Maxim Integrated

Catalog

White LED Current Regulator with 1x/1.5x High-Efficiency Charge Pump

Part	Voltage - Supply (Min)	Dimming	Mounting Type	Current - Output / Channel	Operating Temperature (Max)	Operating Temperature (Min)	Package Length	Package Name	Package Width	Number of Outputs	Voltage - Supply (Max)	Type	Internal Switch(s)	Topology	Frequency	Applications	Package / Case
Analog Devices Inc./Maxim Integrated MAX1570ETE+	2.7 V	PWM	Surface Mount	30 mA	85 °C	-40 °C	4 mm	16-TQFN	4 mm	5	5.5 V	DC DC Regulator	Yes	Switched Capacitor (Charge Pump)	1 MHz	Backlight	16-WQFN Exposed Pad
Analog Devices Inc./Maxim Integrated MAX1570ETE+T	2.7 V	PWM	Surface Mount	30 mA	85 °C	-40 °C	4 mm	16-TQFN	4 mm	5	5.5 V	DC DC Regulator	Yes	Switched Capacitor (Charge Pump)	1 MHz	Backlight	16-WQFN Exposed Pad

Catalog

White LED Current Regulator with 1x/1.5x High-Efficiency Charge Pump

Description

The MAX1570 fractional charge pump drives up to five white LEDs with regulated constant current for uniform intensity. The MAX1570 maintains the highest possible efficiency over the full 1-cell lithium-ion (Li+) battery input voltage range by utilizing a 1x/1.5x fractional charge pump and very-low-dropout current regulators. The MAX1570 operates with 1MHz fixed-frequency switching, allowing for tiny external components. The regulation scheme is optimized to ensure low EMI and low input ripple.An external resistor sets the full-scale LED current, while two digital inputs control on/off and select between three levels of brightness. A pulse-width modulation (PWM) signal can also be used to modulate LED brightness.The MAX1570 is available in 16-pin 4mm x 4mm Thin QFN packaging (0.8mm max height).ApplicationsCell Phones/SmartphonesDigital Cameras and CamcordersPDAs and Palmtop ComputersPortable MP3 PlayersWhite LED Backlighting