Does the Equation Vout=-Iin*Rf Always Apply in Current-to-Voltage Converters?

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In current-to-voltage converters, the equation Vout = -Iin * Rf applies under typical conditions, where Rf is the feedback resistor. However, variations in input current (Iin) and feedback resistance (Rf) can affect the output voltage, especially if the input current exceeds the op-amp's operational limits, typically around 1-10mA. The discussion also highlights that similar circuits, like voltage adders and inverting amplifiers, can be analyzed using the same principle of Vout = Iin * Rf. Understanding the limitations of op-amps is crucial for accurate analysis. Overall, the equation holds true within specified operational ranges and conditions.
Midas_Touch
I have attached a diagram of the circuit I have a question about.

In this current-to-voltage converter circuit, Rf = 1 k ohm. I was wondering if v out would equal Vout=-Iin*Rf where I in is the input current. If I varied the current, say 1-7 amps, would the above equation apply? How about if I varied the Rf? Would the same equation still apply?

Also, since the voltage adder and the inverting amplifier are similar to the current-voltage converter, how can I show that those circuits can be analyzed as current to voltage converter, as in vout = Iin*Rf?

I'd appreciate any suggestions...
 

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Well, yes, except that most opamps are run in the 1-10mA range. Other than that, you are on track.
 
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