View g5130-g5131-series datasheet:

Global Mixed-mode Technology Inc. G5130/G5131 PSM Step-up DC/DC Converter Features General Description 1~4 Cell Alkaline Battery Operating Range The G5130/G5131 boost converter is designed for use Output Voltage Range: 2.5V~5.0V in 0.1V In- of main power source on portable equipments. crements It consist of an oscillator, PSM control logic circuit, an Minimum External Component (L, D, C) embedded power MOS (LX switch), accurate voltage 100KHz Max. Oscillation Frequency reference, error amplifier, feedback resistors, and LX 75% Duty Ratio protection circuit. Up to 80% Efficiency ±2% High Output Voltage Accuracy Only 3 external components (includes 1 inductor, 1 < 100ppm/°C Temperature Coefficient diode and 1 capacitor) are needed to constru