Wondering were to start ...
I have a signal from a fan control head that is 12V when OFF and 0V when 100% ON. Any value between there will vary the speed of the fan.
I would like to convert this signal so it is 0V when OFF and 12V when 100% ON, so I can use a different fan driver that can handle a more powerful fan.
I figured a differential op amp would be a good way to start, as the output voltage would be the difference between the two input voltages. Per the equations if all the resistors are the same value, the overall gain is 1 and thus Vout = V1 - V2. See attached schematic. I bread boarded it (and double checked my inverting and non-inverting terminals were hooked up correctly). Both Inputs are 12V but my output is 3V. I'm using an OP296 with +12V and 0V to the rails.
Can I achieve my desired result using this method? I was also thinking of putting the input signal through inverting opamp and then another summing op amp.
Looking for some advice ... thanks.
I have a signal from a fan control head that is 12V when OFF and 0V when 100% ON. Any value between there will vary the speed of the fan.
I would like to convert this signal so it is 0V when OFF and 12V when 100% ON, so I can use a different fan driver that can handle a more powerful fan.
I figured a differential op amp would be a good way to start, as the output voltage would be the difference between the two input voltages. Per the equations if all the resistors are the same value, the overall gain is 1 and thus Vout = V1 - V2. See attached schematic. I bread boarded it (and double checked my inverting and non-inverting terminals were hooked up correctly). Both Inputs are 12V but my output is 3V. I'm using an OP296 with +12V and 0V to the rails.
Can I achieve my desired result using this method? I was also thinking of putting the input signal through inverting opamp and then another summing op amp.
Looking for some advice ... thanks.
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