Richtek's RT4539 High efficiency white LED driver is suitable for single/dual battery input. The driver consists of six parallel LED strips

     Richtek's RT4539 High efficiency white LED driver is suitable for single/dual battery input to drive LED light strips containing 6 strings in parallel. Available in WL-CSP-20B 1.71x2.371 (BSC) in a 0.4mm pitch package. The internal current receiver supports a maximum ±2% current mismatch to achieve excellent brightness uniformity in each string of leds. To provide sufficient headroom for current aggregation operations, the boost controller monitors the minimum voltage of the feedback pin and adjusts the optimized output voltage to improve power efficiency.

     The RT4539 has a wide input voltage operating range of 2.7V ~ 24v and includes an I²C interface for controlling dimming mode, operating frequency and LED current. Internal 250 mL, 36 V current mode control power switch provides overcurrent protection. The RT4539's switching frequency is adjustable from 300 kHz to 1.6 MHz, which allows flexibility between efficiency and component size.