“This small board is based on the CS5171 boost converter from ON Semiconductor. The board is configured to be used with a single 18650 LiPo battery. The circuit converts single-cell 3.7V LiPo battery voltage to 5V with a load current up to 400mA. Board has been designed to fit on the backside of a single-cell battery holder with a screw. The CS5171 IC is a 280 kHz switching regulator with a high efficiency, 1.5 A integrated switch.”