Pololu Adjustable Step-Up/Step-Down Voltage Regulator S8V3A is a switching regulator (also called a switched-mode power supply (SMPS) or DC-to-DC converter) with a single-ended primary-inductor converter (SEPIC) topology. It takes an input voltage from 1.5 V to 12 V and increases or decreases the voltage to a user-adjustable output voltage between 2 V and 12 V. The input voltage can be higher than, lower than, or equal to the set output voltage, and the voltage is regulated to achieve the set output voltage. This flexibility in input voltage is especially well-suited for battery-powered applications in which the battery voltage begins above the desired output voltage and drops below the target as the battery discharges.
Pololu Adjustable Step-Up/Step-Down Voltage Regulator S8V3A has a shutdown feature that can also be used as an under-voltage protection mechanism for batteries that respond poorly to being over-discharged. The shutdown threshold can be set with one external resistor.
Pololu Adjustable Step-Up/Step-Down Voltage Regulator S8V3A can deliver 300 mA continuous in typical applications where the output voltage is not too far from the input voltage. The regulator has under-voltage protection, and thermal shutdown prevents damage from overheating; the board does not have reverse-voltage protection. For applications where the output is significantly different from the input, a regulator optimized for boosting (stepping up) or bucking (stepping down) is more efficient, but for small applications where efficiency is not a top priority, this board can be a convenient, general-purpose regulator to give your system a wide range of supported input voltages.
Pololu Web Site: https://www.pololu.com/product/2120