5V Powwr Supply Crowbar protection MC3425 (CB14530E)

This circuit is suggested by Motorola in its 1990 Linear Databook. The integrated circuit is no longer common in the market.

Photoelectric Relay (CB23541E)
This circuit is from a Radio Electronics from October 1963. The LDR and transistors are from the...
Voltage divider CA3140 (CB24968E)
The figure shows how to use an operational circuit as a voltage divider. The circuit is from a...
Current regulator with operational (CB21113E)
This is the basic configuration of an operational amplifier as a current regulator. We found it in...