Voltage gain

[libby6295]

For this circuit, how would I calculate a value for R2 that would give a voltage gain of 95v?

[altenbach]

You need to stop attaching word documents with just an embedded image. you can embed images directly into posts here!

You also need to stop posting camera shots of computer screens. Learn how to take screenshots (e.g. alt-[print screen], then paste from the clipboard into your post or edit (trim, etc.) with MS paint first.

You need to stop starting new threads with trivial questions, most having nothing to do with multisim.

[tipa]

MS выдаёт сомнительный результат, так как напряжение не может превышать напряжения питания. Скорее всего виновата модель.

[GGoodwin]

Hi libby6295,

Voltage gain should be unitless.

If you are asking for an output voltage of -95 V, for an inverting amplifier

 Vo             R1
───── = Av = - ────
 Vin            R2

        R1 · Vin       950 kΩ · (- 500 mV)
R2 = - ────────── = - ─────────────────────
           Vo                - 95 V

R2 = 5000 Ω = 5 kΩ

That is a theoretical value. Note however that the operational amplifier is powered from ±15 V so a ±95 V output is not possible.

If you are asking for a voltage gain of -95, for an inverting amplifier

 Vo             R1
───── = Av = - ────
 Vin            R2

        Av       95 kΩ
R2 = - ──── = - ───────
        R1       - 95

R2 = 1000 Ω = 1 kΩ

If the circuit will have a voltage gain of -95, the output voltage will be (500 mV)(-95) = -47.5 V. Again this tends to exceed the ±15 V power supply so a ±47.5 V output is not possible.

In your circuit the input signal is rated in rms. If this is taken into account it will make the theoretical output voltages in the computation even less realizable.

Best regards,

G. Goodwin