This power supply regulator has the following characteristics:
a) very low voltage drop of less than 1V.
b) negligible standby current from 20 to 30 ľA.
c) variable but very stable output.
These characteristics make the circuit practical in some applications compared with the 3-terminal IC regulator which has high voltage drop and standby current
consumption. Specially in battery operated applications, the discrete regulator featured here is highly recommended.
The circuit is basically a series regulator that uses a normal LED to produce the reference voltage. The given component values deliver a variable output from 2V up to
8V. If you intend to increase it up to 16V, change R4 with 220 kiloohms. Eventually, you need to increase the value of P1. The maximum current that can be delivered by the
regulator circuit depends on the type of the series transistor used and the difference between the input and output voltages.
Parts Placement Layout
External Wiring Layout
Electronic Circuits volume 1.0 - Circuit Nr. 60
The complete data of the electronic circuit described above can be found in the following book and is available from Amazon.com.
Click on the image to view the book.