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Level shifter

  1. Dec 13, 2009 #1
    1. The problem statement, all variables and given/known data

    Using the level shifter shown below, design a circuit that will shift a signal from from +/- 25 volts (50 volts P-P) to 0 to 5 volts. Assume R1=R3=100K and R2=R4.
    In answer 1 give the value for Vref with 1 decimal point of precision

    in answer 2 gie the value for R2=R4 in K ohms.

    http://img695.imageshack.us/img695/4536/shifterl.th.jpg [Broken]

    2. Relevant equations

    Vo = (Vin -Vref) R4/(R3+R4) + Vref

    3. The attempt at a solution

    I am just confused where the R2 takes place... do I just plug and chug
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Dec 14, 2009 #2
    Yeah, just plug and chug while maintaining the equalities they tell you to keep. The formula they've made, that you're plugging and chugging into, depends on these equalities.
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