Convert 0-5v DC to 8-18v DC

Discussion in 'The Projects Forum' started by wpnsx, Mar 14, 2011.

  1. wpnsx

    Thread Starter New Member

    Mar 14, 2011
    This is my first post and I apologize if this is somewhere else but I am unable to find it and posting is my last resort.

    I am trying to make a module which will allow me to display an analog output of 0-5vdc as 8-18vdc, on a simple voltage meter. (0 = 8, 5 = 18)

    The supply voltage is a standard 12v automotive battery (13.5vdc)

    I have tried succesfully with an LM258 op amp (summing amplifier), 24v converter and 8v reg but this has lots of stuff and Im hoping there is a much neater way though it is beyond me at this moment. Also the initial 0-5v output will be logged directly (at the same time) so I want this display circuit to have minimal impact on the 0-5v output.

    Any help would be hugely appreciated,

  2. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    Post the schematic of what you have successfully done. Given the constraints it may not be possible to significantly reduce your parts count.
  3. wayneh


    Sep 9, 2010
    Are you familiar with a basic "instrument amplifier" op-amp circuit? It's specifically meant to let you set an offset and scale, more or less exactly what you need.
  4. Kermit2

    AAC Fanatic!

    Feb 5, 2010

    Or just get a 0-5 meter and redraw the scale for 8-18.

  5. wpnsx

    Thread Starter New Member

    Mar 14, 2011
    Thanks heaps for the responses guys!!

    I am realizing that it is difficult (if impossible) to have a voltage out over 13v when the supply voltage is only 13v, therefore the 24v converter is necessary.

    I looked at the instrumentation amplifiers but I think once again I will need a supply voltage greater than my maximum display voltage.

    The simple voltmeter with the altered scale may be a winner for me cause its just so simple and that's how i want this thing to be. Unless I come across a cheap 24v converter.

    Thanks once again for your help guys.