Build A Smart Battery Charger Using A Single-Transistor Circuit  The following automatic battery-charger design is created with a circuit that could qualify as the simplest window comparator ever built around a single transistor . It starts charging when the battery voltage drops beyond a preset value, and it stops when an upper preset voltage is attained.

Read more about
Build A Smart Battery Charger Using A Single-Transistor Circuit
at electronicdesign.com
Website

Build A Smart Battery Charger Using A Single-Transistor Circuit