austriamicrosystems AG is now ams AG The technical content of this austriamicrosystems datasheet is still valid. Contact information: Headquarters: ams AG Tobelbaderstrasse 30 8141 Unterpremstaetten, Austria Tel: +43 (0) 3136 500 0 e-Mail: ams sales ams.com Please visit our website at www.ams.com Datasheet AS3647/47B 1600mA High Current LED Flash Driver 1 General Description 2 Key Features High efficiency 4MHz fixed frequency DCDC Boost The AS3647/47B is an inductive high efficient DCDC converter with soft start allows small coils step up converter with two current sinks. The DCDC step up converter operates at a fixed frequency of 4MHz - Stable even in coil current limit and includes soft startup to allow easy integration into LED current adjustable up to 1600mA noise sensitive RF systems. The two current sinks can operate in flash / torch / assist (=video) light modes. Automatic current adjustment for low battery voltage The AS3647/47B includes flash timeout, overvoltage, overtemperature, undervoltage and LED short circuit PWM operation for lower output current for reliable protection functions. A TXMASK/TORCH function light output of the LED running at 31.25kHz to avoid reduces the flash current in case of parallel operation to audible noise the RF power amplifier and avoids a system shutdown. Protection functions: Alternatively this pin can be used to directly operate the Automatic Flash Timeout timer to protect the LED(s) torch light directly. Overvoltage and undervoltage Protection 2 The AS3647/47B is controlled by an I C interface and Overtemperature Protection has a hardware automatic shutdown if SCL=0 for LED short/open circuit protection 100ms. Therefore no additional enable input is required 2 I C Interface with automatic shutdown for shutting down of the device once the system shuts 5V constant voltage mode operation down. Available in tiny WL-CSP Packages, 13 balls 0.5mm pitch 2.25x1.5x0.6mm, 15 balls 0.4mm pitch 2.25x1.5x0.5mm package size The AS3647/47B is available in a space-saving WL- CSP package measuring only 2.25x1.5x0.6mm 3 Applications (AS3647B: 2.25x1.5x0.5mm) and operates over the - 30C to +85C temperature range. Flash/torch/videolight for smartphones, feature-phones, tablets, DSCs, DVCs Figure 1. Typical Operating Circuit & ) *+ * % % % * .- / & % ,( - + & % 0 & ( ( ( ( ( AS3647/47B www.austriamicrosystems.com/AS3647 1.5-4 1 - 37 (ptr) ams AG Technical content still valid