This circuit shows how to add a 1st regulator to a source that already has a step for this purpose. The circuit was found in an American power supply documentation.
Using bipolar, FETs and unijunction this long-lasting timer can reach 10 hours with good quality...
The configuration shown is from the National Semiconductor Linear Applications Handbook. The...
This shield circuit uses a common CMOS port. The voltage depends on the interfaced logic. The...