Asset Publisher

AS3644 LED Flash Driver

320mA single LED flash driver


  • 4MHz fixed frequency DC-DC
  • Small chip-scale package
  • Overvoltage, overtemperature, undervoltage and LED short circuit protection functions


  • Tiny external coils
  • Small system size
  • High system safety

Product parameters

Topology Inductive
DC-DC Frequency [MHz] 4
Performance (ILed Max.) [mA] 320
- [Vout Max.] 5.5
LED Channels [Curr. Sinks] 1
- [Curr. Source] High-side
- [Flash LEDs] 1
- [Indicator LED] Flash LED
Interfaces [I²C] Yes
- [Enable]
Safety Features [TimeOut] Yes
- [TXMask]
Package WL-CSP-6 (1.5x1.1)-0.5p

General Description

The AS3644 is an inductive high efficient DC-DC step-up converter driving one current source. It operates at a fixed frequency of 4MHz and includes a soft startup to allow easy integration into noise sensitive RF systems. The current source operates in flash/torch/assist (video/autofocus) and indicator mode. The AS3644 includes flash timer, overvoltage, overtemperature, undervoltage and LED short circuit protection functions.

This product suits for the following applications:

  • Smallest size LED flash solution for mobile phones


Name Type Description Language Software Eval SW English Software Eval SW 1v24 English

Technical Documents

Name Type Description Version Language
AS3644_AN000128_1-00.pdf Application Note Radiation measurement 1-00 English
AS3644_BD000264_1-00.png Block Diagram AS3644 Block Diagram 1-00 English
AS3644_DS000216_1-00.pdf Datasheet Document version 1.2.2 1-00 English
AS11xx_AS13xx_AS17xx_AS349x_AS36xx_EN000160_1-00.pdf EoL Notification AS11xx_AS13xx_AS17xx_AS349x_AS36xx (issued 2018-Oct) 1-00 English
AS3644_UG000194_1-00.pdf User Guide Demo board 1-00 English

Asset Publisher