MCP6041 Op Amp Switched Non-Inverting Amplifier

This circuit uses the MCP6041 Op Amp as a switched non-inverting gain stage. SW1 connects the sine source to the non-inverting input, RF and RG set the closed-loop gain, and the output drives a green LED load through RL so voltage gain and load current can be inspected together.

Suggested Applications

• Amplifying a small AC control or sensor signal before an indicator or follow-on analog stage.
• Demonstrating how a non-inverting op amp stage responds when an input path is opened or closed.
• Comparing input voltage, output voltage, and LED/load current in a practical closed-loop amplifier stage.

Featured Component

The MCP6041 Op Amp uses the MCP6041 SPICE macromodel in this demo. It is powered from split +/-15 V supplies and used in a feedback amplifier so its closed-loop behavior, output swing, and load-drive behavior are visible in one circuit.

Design Context

RF is 1 kOhm from the output to the inverting input, and RG is 1 kOhm from the inverting input to ground. The ideal non-inverting gain is 1 + RF/RG = 2 V/V. The input source is a 1 V peak, 1 Hz sine wave, so VOUT should be about 2 V peak while the op amp remains inside its supply and output-current limits.

The VIN and VOUT probes show the applied input and amplified output. The current probe in the LED branch shows how output swing translates into load current through the 100 ohm resistor and green LED. At this signal level, the output should forward-bias the green LED branch on positive peaks and produce measurable load current through RL.

Expected Behavior

With SW1 closed, VOUT should follow VIN with approximately 2x non-inverting gain and remain centered near 0 V. With SW1 open, the input path is interrupted, so the output should no longer track the sine-wave source in the same way. Realistic output swing, bandwidth, and load-current behavior depend on the op amp macromodel and the selected supply rails.

Suggested Experiments

Toggle SW1, change RF or RG to adjust gain, increase the input amplitude to explore output clipping, or change RL to see how the LED load current affects the output waveform.