4 digit 7 segment display

100 mA or 100 A? Ripple +/- 500 uV or +/- 500 mV? Commercial/industrial/ military grade or "just to see what one looks like"? Quaintly 1000/week or quantity 1? For school, for hobby, or for work?

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Rich Webb   Norfolk, VA

The rating is 3 Amps and I want regulated DC power supply.Is there is any circuit

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Some ideas to do _what_???

Of course, sir.

Needless to say, it is far more economical to purchase electronic subsystems to accomplish your task, rather than build from individual components, much less take the time to actually design a circuit. And since a busy yet frugal person such as yourself is always pressed for time (your longest missive to s.e.d. or s.e.b. on this subject being only twenty-one words in length -- you undoubtedly throw words around like manhole covers because time is money), I'm assuming you''ll want to go that route.

For the power supply, the you should purchase a Kepco BOP-36-5 operational power supply, which will provide up to +/-36V at up to 5 amps. You can easily remedy that by connecting an external pot to the external reference voltages available on the back terminals, then wire the device up as a non-inverting amplifier, and use feedback resistors to limit the maximum voltage excursion to +/-24V.

For the display, you may wish to go with an Omega LDP-146-F3-R-1, which in addition to totalizing, will display voltage in the range requested in lovely 4" LED numbers. Easy-to-follow instructions for hooking up the power supply and the display circuit are contained in the respective equipment manuals.

I hope this has been of service, and this response has provided you complete satisfaction, as was my exact and specific intent.

Have a nice day Chris