This discussion focuses on configuring an operational amplifier (op-amp) to achieve a positive gain of less than one, specifically with a high reference voltage instead of ground. The user seeks to design a circuit where an input of 3.3V results in an output of 3.3V, and an input of 0V yields an output of approximately 1.4V. While the user initially struggled with the necessity of using an op-amp for this configuration, they ultimately realized that it is feasible. The conversation highlights the potential use of a resistor divider as an alternative to achieve the desired output without an op-amp.
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JerryG said:I am trying to setup a circuit with an op-amp that is referenced to high rather than ground and has a positive gain less than one. So for instance, my circuite has power rails at ground and 3.3v. I want an input of 3.3v to give an output of 3.3v and i want an input of 0 to give an output of around 1.4v. I can do the resistor calculations. I'm just not sure what that configuration would look like.