NICAD Charger

by: F Harq

This circuit uses constant current LEDs to adjust charging current. It uses LEDs that pass a constant current of about 15 mA for an applied voltage range of 2 to 18 V. They can be paralleled to give any multiple of 15 mA and the light up when current is flowing. The circuit will charger a single cell at 51, 30, or 45 mA, or cells in series up to the rated supply voltage limit (about 14 V)