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How can I shift analog voltages ranging from -5V...+5V to 0V...5V without using an op amp? I was thinking about some kind of current mirror?

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    \$\begingroup\$ What sort of signals? What is the application? \$\endgroup\$ Apr 4 at 19:04
  • \$\begingroup\$ What is the motivation for not using an op amp? \$\endgroup\$ Apr 5 at 4:08

2 Answers 2

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You just need a simple voltage divider.

schematic

simulate this circuit – Schematic created using CircuitLab

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  • \$\begingroup\$ For high-speed signals it helps to add capacitors in parallel with the resistors, creating a frequency-compensated divider. \$\endgroup\$
    – jpa
    Apr 5 at 5:38
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Provided your source can provide far more current than what you need at the output (without disturbing your source), you have a very simple solution, with just 2 resistors : a voltage divider towards +5V :

schematic

simulate this circuit – Schematic created using CircuitLab

You get Vout = R1/(R1+R2) * Vin + R2/(R1+R2) * 5V Which simplifies to Vout = (Vin + 5V)/2 = 2.5V + Vin/2 if R1=R2 So Vin=-5V -> Vout=0V ; Vin=0V -> 2.5V ; Vin=5V -> Vout=5V

Note that the current flowing between Vin and 5V needs to be far bigger than the current flowing to Vout if you want accurate results. This might be blocking depending of your source and load (if your source is weak, you need big values of resistors, which means you can draw only very little current on Vout).

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