741 Unity-Gain Voltage Follower

This circuit uses a 741 operational amplifier as a unity-gain voltage follower. The output is fed directly back to the inverting input, so the amplifier buffers the input waveform while providing a lower-impedance output for the load.

Suggested Applications

• Buffering sensor or reference signals before they drive another stage.
• Isolating a high-impedance signal source from a lower-impedance load.
• Learning how negative feedback forces an op amp output to follow the non-inverting input.

Featured Component

The 741 Op Amp is a classic general-purpose operational amplifier model. In this follower configuration, it demonstrates closed-loop unity gain behavior with a small 1 kHz AC input and split +/-15 V supplies.

Design Context

The input source applies a 0.5 V peak sine wave to the non-inverting input. The output is connected directly to the inverting input, creating 100% negative feedback. A 10 kOhm load represents a light downstream load.

Expected Behavior

The VOUT trace should closely follow VIN with approximately unity gain. Small differences reflect the finite open-loop gain, bandwidth, and output behavior of the 741 model.

Suggested Experiments

Try increasing the input frequency, changing the load resistor, or adding a DC offset to see where the follower begins to show bandwidth, loading, or output-swing limits.