Found in American documentation from the 1980s, this circuit makes use of components of the time, which are uncommon today. The circuit detects the approach using a sensor formed by metal plates.
By changing the zener, other output voltages can be obtained for this symmetrical power supply. With...
The circuit shown is from the 1994 Linear Applications Handbook by National Semiconductor. Other...
This circuit is from the 1994 Linear Applications Handbook, published by National Semiconductor, which is...