LM3642

Product Folder Sample & Buy Technical Documents Tools & Software Support & Community LM3642 SNVS891H – SEPTEMBER 2012 – REVISED SEPTEMBER 2015 LM3642 1.5-A Synchronous Boost LED Flash Driver With High-Side Current Source 1 Features 1 1.5-A High-Side Current Source for Single LED > 85% Efficiency in Torch Mode (at 100 mA) and Flash Mode (at 1 A to 1.5 A) Accurate Programmable Flash LED Current from 93 mA to 1.5 A Accurate Programmable Torch LED Currents: – 48.4 mA to 375 mA – 24 mA to 187 mA (LT option) Small Solution Size: < 20 mm2 Soft-Start Operation for Battery Protection Hardware Strobe Enable Synchronization Input for RF Power Amplifier Pulse Events VIN Flash Monitor Optimization 400-kHz I2C-Compatible Interface 0.5-mm Pitch, 9-Bump DSBGA 2 Applications Camera Phone LED Flash 3 Description The LM3642 is a 4-MHz fixed-frequency synchronous boost converter plus 1.5-A constant current driver for a high-current white LED. The high-side current source allows for grounded cathode LED operation providing Flash current up to 1.5 A. An adaptive regulation method ensures the current source remains in regulation and maximizes efficiency. The LM3642 is controlled via an I2C-compatible interface. Features include a hardware flash enable (STROBE) allowing a logic input to trigger the flash pulse as well as a TX input which forces the flash pulse into a low-current Torch Mode, allowing for synchronization to RF power amplifier events or other high-current co...