Both the operational amplifier and the diodes admit equivalents in this circuit suggested by National Semiconductor. The power source must be symmetrical, and the circuit curve resembles an ideal diode.
The figure shows three circuits for using headphones in amplifiers with speakers that do not have...
In this charger, the charging current is basically limited by the LEDs. The transformer is a low...
This configuration is from an old integrated circuit manual. The circuit can be applied to modern...