The RT4505 is a maximum 4MHz frequency synchronous Boost converter plus a 1.5A 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 1.5A. An adaptive regulation method ensures the current source remains in regulation and maximizes efficiency.
The RT4505 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, allowing for synchronization to RF power amplifier events or other high-current conditions.
The maximum 4MHz switching frequency, over-voltage protection and adjustable current limit settings allow the use of tiny, low-profile inductors and ceramic capacitors. The device is available in a small WL-CSP-9B 1.3x1.37 (BSC) package, and operates within the -40°C to 85°C temperature range.