Datasheet4U Logo Datasheet4U.com

A8431 Datasheet White Led Driver Constant Current Step-up Converter

Manufacturer: Allegro MicroSystems

Overview: .. Preliminary Data Sheet Subject to Change without Notice April 5, 2005 A8431 The A8431 is a noninverting boost dc-dc converter that provides a programmable constant current output up to 32 V for driving white LEDs in series.The A8431 also offers an OVP (overvoltage protection) pin. Driving the LEDs in series ensures identical currents and uniform brightness. Up to four white LEDs can be driven at 20 mA from a single cell Li-ion or a multicell NiMH power source. Up to two parallel strings of eight white LEDs can be driven at 20 mA by increasing the supply voltage up to 10 V. The A8431 incorporates a power switch and a feedback sense amplifier to provide a solution with minimum external ponents. The output current can be set by adjusting a single external sense resistor and can be varied with a voltage or a filtered PWM signal when dimming control is required. The high switching frequency of 1.2 MHz allows the use of small inductor and capacitor values. The A8431 is provided in a 0.75 mm high, 6-pin, 2 x 3 mm MLP package. It is lead (Pb) free, with 100% matte tin leadframe plating.

Key Features

  • Output voltage up to 32 V (OVP level) 2.5 V to 10 V input Drives up to 4 LEDs at 20 mA from a 2.5 V supply Drives up to 5 LEDs at 20 mA from a 3 V supply 1.2 MHz switching frequency 300 mA switch current limit 1 µA shutdown current OVP pin eliminates the need for an external Zener diode on the output.

More Datasheets from Allegro MicroSystems

Part Number Description
A8430 White LED Driver Constant Current Step-up Converter
A8434 6-Channel High Efficiency Charge Pump White LED Driver
A8435 High Efficiency Charge Pump White LED Driver
A8436 Photoflash Capacitor Charger
A8437 Mobile Phone Xenon Photoflash Capacitor Charger
A8438 Photoflash Capacitor Charger
A8439 Photoflash Capacitor Charger
A8447 High Voltage Step Down Regulator
A8483 Step-up Converter
A8498 Wide Input Voltage 3.0A Step Down Regulator

A8431 Distributor