The circuit shown is from 1994 National Semiconductor documentation but can be implemented with more modern operational amplifiers. The power supply must be symmetrical.
What differentiates the CIR8139 circuit is the use of two inverter ports to trigger the transistor that...
The battery charger suggested in the figure has its current limited by resistor R1. This component may...
This circuit with increased power output was found in the November 1974 Radio Electronics...