Universal Power Supply Module 3V-30V

This universal power supply circuit provides a variable voltage between 3-30 V. The power supply provides maximum current 1.5 A and with a few modifications and additions to modules can provide a higher current.

Adjustable regulator LM317 (U1) offers short-circuit protection and automatic current limiting at 1.5A. The input voltage to the regulator is supplied by DB1, a 4 A 100 PIV full-wave bridge rectifier. Capacitor C1 gives initial filtering. U1 provides extra electronic filtering included in the regulating function. The output level of the regulator is set by trim-pot R1. To prevent high-frequency oscillation Bypass capacitor added to the input and output of U1 . The current output of the transformer should be no less than 1.8 times the rated continuous-duty output of the supply. Which means that a 1.5-A supply should apply a 2.7-A transformer. For light or intermittent loads, a smaller 2.0-A transformer should be enough.

Wiring a 2nd Adjustable regulator LM317, U2, in parallel with U1 can be a quick and clean method to increase the current limiting threshold of the universal power supply to 3 A without having to sacrifice short-circuit protection. When more than 3 A is needed, the regulator module may be used to drive the base of one or more pass-transistors (see Fig. B).

psu

Share
Published by
psu

Recent Posts

Universal Battery Charger for Charging up to 18V Cell

This universal battery charger has regulated output voltage which can be adjusted as you need.…

5 years ago

Auto Switch-Off Power Supply (Variable Output 3.7V to 8.7V)

Here is the auto switch-off power supply which will turn off itself when there is…

6 years ago

High Voltage, Low Current Power Supply (2000VDC from 15VDC)

This is a high voltage, low current power supply capable to deliver 2000VDC output from…

6 years ago

15V 1A Regulated Symmetrical Power Supply

This is the easy built 15V 1A regulated symmetrical power supply capable to deliver stabilized…

7 years ago

12V / 3A Regulated Power Supply

Here we provide a powerful 12V / 3A regulated power supply circuit. Of course the…

7 years ago

How To Repair Computer Power Supply

If the power supply is damaged or does not work, the computer also will not…

7 years ago