• Input Voltage Range: 2.7V to 5.5V

• Drives up to 8 LEDs at 27mA Each

• One Single Wire Interface

• 16-Step Brightness Control

• High Efficiency by Fractional Conversion with 1× and 1.5× Modes

• Switching Frequency: 0.93MHz

• Regulated Output Current with ±4.8% Matching

• Internal Soft-Start Limits Inrush Current

• Low Input Ripple and Low EMI

• Over-Current and Over-Temperature Protection

• Under-Voltage Lockout with Hysteresis

• Available in Green TQFN-3×3-20L Package

The SGM3146 is a high performance white LED driver. It integrates current sources and automatic mode selection charge pump. The part maintains the high efficiency by utilizing a 1×/1.5× fractional charge pump and low dropout current sources. The small equivalent 1× mode open loop resistance and ultra-low dropout voltage of current source extend the operating time of 1× mode and optimize the efficiency of Li-ion battery in white LED applications.

The SGM3146 supports up to 8 white LEDs and regulates a constant current which the initial value can be set by an internal resistor. The part implements a 4-bit DAC for brightness control. Users can easily configure the LED current from 1.65mA to 27mA by a serial pulse. The dimming of white LEDs current can be achieved by applying a pulse signal to the EN/SET pin. There are totally 16 steps of current could be set by users. The operating voltage range is 2.7V to 5.5V. Internal soft-start circuitry effectively reduces the in-rush current while both start-up and mode transition.