AS3643

valid Datasheet AS3643 1300mA High Current LED Flash Driver 1 General Description The AS3643 is an inductive high efficient DCDC step up converter with two current sinks. The DCDC step up converter operates at a fixed frequency of 4MHz and includes soft startup to allow easy integration into noise sensitive RF systems. The two current sinks can operate in flash / torch / assist (=video) light modes. The AS3643 includes flash timeout, overvoltage, overtemperature, undervoltage and LED short circuit protection functions. A TXMASK/TORCH function reduces the flash current in case of parallel operation to the RF power amplifier and avoids a system shutdown. Alternatively this pin can be used to directly operate the torch light directly. The AS3643 is controlled by an I2C interface and has a hardware automatic shutdown if SCL=0 for 100ms. Therefore no additional enable input is required for shutting down of the device once the system shuts down. The AS3643 is available in a space-saving WL-CSP package measuring only 2.25x1.5x0.6mm and operates over the -30ºC to +85ºC temperature range. Figure 1. Typical Operating Circuit 2 Key Features High efficiency 4MHz fixed frequency DCDC Boost converter with soft start allows small coils - Stable even in coil current limit LED current adjustable up to 1300mA Automatic current adjustment for low battery voltage PWM operation for lower output current for reliable light output of the LED; running at 31.25kHz to avoid audible noise ...