Utility Power Supply

Posted on Feb 4, 2014

Its main feature is a selection of outputs at standard fixed voltages used in electronics. Because the outputs are fixed you do not have to worry if the voltage is correct, you just plug the wire in. It is quick and easy to use. You will probably still need a conventional variable power supply to test circuits over a range of voltages - but this is the one that you will use for day-to-day development. This power supply was

Utility Power Supply
Click here to download the full size of the above Circuit.

intended to be straight forward and easy to use without controls that needed to be adjusted. It should supply all the standard voltages commonly used in electronic circuits at 500mA or more. The outputs are enabled by the output switch. This instantaneously disconnects the output, compared to the power switch, which, when turned off, can leave the outputs powered for some seconds due to the charge in the filter capacitors. The only downside is that there is no provision for current limiting. in the event of a short or something similar going wrong this power supply will attempt to drive 1. 5 amps through your test circuit. Current limiting was left out because it would be difficult to properly implement and it would result in something that had to be adjusted - which was just what this project was trying to avoid. Standard range fixed resistors are used to set the output voltages, and because of this careful attention given was to ensure that the values selected gave an result that was as close as possible to the desired voltage. In this design the maximum error due to the values of the resistors chosen is 0. 89% and in most cases it is less than 0. 5%. These resistors are specified as 1% tolerance and the LM317 and LM337 regulators have a tolerance of 1% also. So, the maximum error would be the sum of these (ie, 3%), but in most cases would be somewhat less. This is much better than the standard tolerance for these...

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    Four-Quadrant Dimmer
    Phase Shifter
    555 Fm Circuit Circuit
    Electronic Siren based NE555
    All Transmitter & Receiver schematics
    Timers and Counters in AT89S52
    timer 555 schematic
    Miniature FM transmitter circuit
    4-input mini Logic Analyzer
    Constitute a CMOS circuit time adjustment of a spot welder