Loublet Schematic

Build a 3V Battery To 5V Dc/Dc Converter Circuits Diagram. A common power-supply requirement involves converting a 2.4- or 3-V battery voltage to a 5-V logic supply. This schema converts 3 V to 5 V at 40 mA with 85% efficiency. When Ic (pin 6) is driven low, the output voltage will be the battery voltage minus the drop across diode Dl. 

The optional schemary that uses CI, R3, and R4 lowers the oscillator frequency when the battery voltage falls to 2.0 V. This lower frequency maintains the output-power capability of the schema by increasing the peak inductor current, which compensates for the reduced battery voltage.