This regulator can be controlled by a logic signal. The circuit is from an Electronics Now from the 90s. Note that the switching transistor is before the integrated circuit.
This battery monitor circuit with the TLV379 low voltage operational amplifier was obtained in the...
We got this circuit from Radio Electronics from July 1990. The circuit mimics the sound of the red...
This configuration often addressed on this site is from a 2000 documentation. The circuit can be...