AS3685B - 1A Photoflash Driver
Capacitive high current 1A single LED Photoflash Driver
Description
The AS3685B is low noise high efficiency photoflash driver. Its capacitive charge-pump operates in 1:1, 1:1.5 and 1:2 modes. The charge-pump mode switching is done automatically.
The AS3685B can drive one flash LED up to 1000mA current. It supports flash/torch and indicator mode for the flash LED. Additionally the AS3685B limits the flash time automatically to protect the flash LED.
Through the easy configurable direct-control interface three current levels are programmable.
The AS3685B is available in a tiny 12 pin WL-CSP or in a 10 pin DFN package.
AS3685 variants:
- AS3685A: "direct control" interface (three selectable currents)
- AS3685B: "single wire" or "two-wire" interface (17 selectable currents)
- AS3685C: "I2C" interface for full programming
- An additional variant locks the 1:2 CP mode (see datasheet for more info)
Key Features
- High Efficiency capactive charge pump (1:1, 1:1.5, 1:2)
- 1:2 CP mode can be disabled (see datasheet for variant)
- Automatic CP mode switching
- LED cathode disconnect in shut-down
- Overtemperature Protection
- Flash LED timeout protection (800ms)
- Packages:
- DFN10 3x3mm
- WL-CSP12 2x1.5mm
Applications
- Mobile phones
- Smart phones
- Digital Still Cameras (DSC)
Block Diagram for AS3685B - 1A Photoflash Driver
AS3685A/B - 1A Low-Noise High-Efficiency Capacitive Charge Pump Block Diagram