The SGM3146 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 SGM3146 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 SGM3146 supports up to 8 LEDs for 27mA maximum current per string. The LED reference current is set through an internal resistor. The SGM3146 contains a 4-bit digital-to-analog converter for 16-step LED current control. The LED current can be set between 1.65mA and 27mA by a serial pulse input signal into the EN/SET pin. Built-in soft-start circuitry avoids excessive inrush current during startup and mode transition.
The SGM3146 is available in a Green TQFN-3×3-20L package. It operates over an ambient temperature range of -40℃ to +85℃.
Input Voltage Range: 2.7V to 5.5V
Support up to 8 LEDs at 27mA Each
16-Step LED Brightness Control through One-Wire Interface
1× and 1.5× Charge Pump for High Conversion Efficiency
Switching Frequency: 0.93MHz
±4.8% 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 a in Green TQFN-3×3-20L Package
White LED Backlighting
Mobile Phones, MP3s
Digital Still Cameras
LCD Displays
