6-Channel Charge Pump White LED Driver with Low Dropout Current Source
6-Channel Charge Pump White LED Driver with Low Dropout Current Source

The SGM3138 is a current-regulated white LED driver with integrated low dropout current sources and a high efficiency charge pump. The charge pump has automatically selectable 1×/1.5× fractional operation modes. The SGM3138 is well suited for white LED applications powered by a Li-Ion battery due to small equivalent open-loop resistance in 1× mode.

The supply voltage operates from 2.7V to 5.5V. The SGM3138 supports up to 6 LEDs for total maximum 120mA current. The LED reference current is set through an internal resistor. The SGM3138 contains a 4-bit digital-to-analog converter for 16-step LED current control. The LED current can be set between 1.25mA and 20mA by a serial pulse input signal into the EN/SET pin.

The SGM3138 provides less than 1μA shutdown current and soft-start function. Built-in soft-start circuitry avoids excessive inrush current during startup and mode transition.

The SGM3138 is available in a Green TQFN-3×3-16L package. It operates over an ambient temperature range of -40 to +85.



  • Input Voltage Range: 2.7V to 5.5V

  • Support to 6 LEDs at 20mA Each

  • 16-Step Brightness Control Through One-Wire Interface

  • 1× and 1.5× Charge Pump for High Conversion Efficiency

  • Switching Frequency: 1MHz

  • ±5% Regulated LED Current Matching

  • Built-in Soft-Start for Reducing Inrush Current

  • Low Input Ripple and Low EMI

  • Protection Features

    Over-Current Protection

    Under-Voltage Lockout

    Thermal Shutdown

  • Operating Temperature Range: -40 to +85

  • Available in a Green TQFN-3×3-16L Package


White LED Backlighting

Mobile Phones, MP3s

Digital Still Cameras

LCD Displays

Part Number Status Package Pins Pb-Free Temp Range
SGM3138YTQ16G/TR Production TQFN-3×3-16L 16 Y -40℃ to +85℃ Samples