Not really homework, as the challenge was set by my self, but looking for advice anyway.
Been trying to get up to speed on op amp theory.
I am trying to simplify a circuit diagram,
The circuit is a single supply 8 volts.
There are two inputs, 0.5 to 5V, going through buffers then potentiometers to allow for adjustment, then they need to be summed and inverted so a rising voltage becomes a falling voltage, so I'm doing this through a difference amp which has an adjustable reference on the positive input to allow level shifting up & down, this is also with a potentiometer coming directly off the power supply, rather than the "ideal" setups I've seen using a voltage divider to virtual ground.
Questions are:
Is this assumption correct?
Been trying to get up to speed on op amp theory.
I am trying to simplify a circuit diagram,
The circuit is a single supply 8 volts.
There are two inputs, 0.5 to 5V, going through buffers then potentiometers to allow for adjustment, then they need to be summed and inverted so a rising voltage becomes a falling voltage, so I'm doing this through a difference amp which has an adjustable reference on the positive input to allow level shifting up & down, this is also with a potentiometer coming directly off the power supply, rather than the "ideal" setups I've seen using a voltage divider to virtual ground.
Questions are:
- Is there a fundamental problem in using a difference amp to sum on the negative input?
- As I am not looking for a gain at this stage, can I eliminate the resistor in the feedback loop, on the diff amp and the two resistors on the inputs and supply the difference amp negative input directly from the two input pot's?
Is this assumption correct?
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