This circuit was obtained in an old Elektor and can be adapted to use white power LEDs. The transistor must be equipped with a heat sink. The circuit has a battery charger.
The TPA3100D2 integrated circuit from Texas Instruments (www.ti.com) consists of an efficient...
This circuit was found in a 1965 General Electric publication. The circuit can be adapted to...
This circuit, which combines a bipolar with any JFET, was found in the April 1993 issue of...