Datasheet Summary
White LED Charge Pump Current Source with PWM Brightness Control
GENERAL DESCRIPTION
The SGM3124 is a charge pump with PWM brightness control for white LED supplies in LCD display backlight applications. The supply voltage ranges from 2.7V to 5.5V, it is ideally suited for all applications powered by a single Li-ion battery cell or three to four NiCd, NiMH, or alkaline battery cells.
The device provides a constant current for each LED, and the initial current value can be set by an external resistor. High efficiency is achieved by utilizing a 1×/1.5× fractional conversion technique in bination with very low dropout current sources.
The SGM3124 is capable of driving up to three...