Op-Amp Inverting Amplifier: Circuit, Measurements and Online Simulator
To build this Op-Amp Inverting Amplifier circuit you need a function generator, an oscilloscope, a TL071 op-amp, a 1 kΩ resistor, a 10 kΩ resistor and two 9 V batteries. A TL071 with Rin = 1 kΩ and Rf = 10 kΩ on ±9 V batteries. A 0.5 Vpp, 1 kHz sine comes out as 5 Vpp, upside down. Make the 12 connections in the wiring table, press Run, and : CH2 is ten times CH1 and inverted. Turn the generator's amplitude past 1.5 Vpp and watch the output clip at the rails.
Open this circuit in the free Electronics bench simulator
Parts list
| Qty | Part | What it does |
|---|---|---|
| 1 | Function Generator | Sine, square, triangle or sawtooth from 1 Hz to 100 kHz, into a 50 Ω output. COM is earth. Watch it on the oscilloscope. |
| 1 | Oscilloscope | Two channels against earth (GND). Turn TIME/DIV and VOLTS/DIV to fit the wave, set the trigger level to steady it, and read Vpp, RMS and frequency. X-Y mode draws Lissajous figures. Choose a digital (DSO) or phosphor (CRO) screen. |
| 1 | TL071 op-amp | Amplifies IN+ − IN− enormously; with feedback from OUT to IN− it becomes a precise amplifier (gain −Rf/Rin). Power it from V+ and V−. |
| 1 | 1 kΩ resistor | Limits current. 220 Ω in series with an LED; 10 kΩ as a pull-up or pull-down. |
| 1 | 10 kΩ resistor | Limits current. 220 Ω in series with an LED; 10 kΩ as a pull-up or pull-down. |
| 2 | 9 V battery | A DC source with a little internal resistance. + is the longer terminal. |
Wiring
| # | From | To |
|---|---|---|
| 1 | Function Generator OUT | 1 kΩ resistor leg 1 |
| 2 | 1 kΩ resistor leg 2 | TL071 op-amp IN- |
| 3 | TL071 op-amp IN- | 10 kΩ resistor leg 1 |
| 4 | 10 kΩ resistor leg 2 | TL071 op-amp OUT |
| 5 | TL071 op-amp IN+ | Function Generator COM |
| 6 | 9 V battery (b1) + | TL071 op-amp V+ |
| 7 | 9 V battery (b1) - | Function Generator COM |
| 8 | 9 V battery (b2) + | Function Generator COM |
| 9 | 9 V battery (b2) - | TL071 op-amp V- |
| 10 | Function Generator OUT | Oscilloscope CH1 |
| 11 | TL071 op-amp OUT | Oscilloscope CH2 |
| 12 | Function Generator COM | Oscilloscope GND |
Step by step
- Open the electronics bench. Open the BitForBytes Embedded Lab in your browser. A circuit with no microcontroller runs on the analog bench: no install or account is needed.
- Add the parts. Add a function generator, an oscilloscope, a TL071 op-amp, a 1 kΩ resistor, a 10 kΩ resistor and two 9 V batteries from the parts palette (Instruments, Power, Passive and Semiconductors).
- Wire 1. Connect Function Generator OUT to 1 kΩ resistor leg 1.
- Wire 2. Connect 1 kΩ resistor leg 2 to TL071 op-amp IN-.
- Wire 3. Connect TL071 op-amp IN- to 10 kΩ resistor leg 1.
- Wire 4. Connect 10 kΩ resistor leg 2 to TL071 op-amp OUT.
- Wire 5. Connect TL071 op-amp IN+ to Function Generator COM.
- Wire 6. Connect 9 V battery (b1) + to TL071 op-amp V+.
- Wire 7. Connect 9 V battery (b1) - to Function Generator COM.
- Wire 8. Connect 9 V battery (b2) + to Function Generator COM.
- Wire 9. Connect 9 V battery (b2) - to TL071 op-amp V-.
- Wire 10. Connect Function Generator OUT to Oscilloscope CH1.
- Wire 11. Connect TL071 op-amp OUT to Oscilloscope CH2.
- Wire 12. Connect Function Generator COM to Oscilloscope GND.
- Run and measure. Press Run: CH2 is ten times CH1 and inverted. Turn the generator's amplitude past 1.5 Vpp and watch the output clip at the rails.
Lab sheet
// Electronics bench: inverting amplifier
//
// Gain = −Rf / Rin = −10 kΩ / 1 kΩ = −10.
// Two 9 V batteries make ±9 V: the middle is ground (the scope's earth).
// IN+ to ground, IN− is a "virtual ground": Rin feeds it, Rf feeds back from OUT.
What to try
Press Run: CH2 is ten times CH1 and inverted. Turn the generator's amplitude past 1.5 Vpp and watch the output clip at the rails.
Frequently asked questions
How do I wire the Op-Amp Inverting Amplifier circuit?
Make 12 connections: Function Generator OUT to 1 kΩ resistor leg 1; 1 kΩ resistor leg 2 to TL071 op-amp IN-; TL071 op-amp IN- to 10 kΩ resistor leg 1; 10 kΩ resistor leg 2 to TL071 op-amp OUT; TL071 op-amp IN+ to Function Generator COM; 9 V battery (b1) + to TL071 op-amp V+; 9 V battery (b1) - to Function Generator COM; 9 V battery (b2) + to Function Generator COM; 9 V battery (b2) - to TL071 op-amp V-; Function Generator OUT to Oscilloscope CH1; TL071 op-amp OUT to Oscilloscope CH2; Function Generator COM to Oscilloscope GND.
What parts do I need for the Op-Amp Inverting Amplifier?
A function generator, an oscilloscope, a TL071 op-amp, a 1 kΩ resistor, a 10 kΩ resistor and two 9 V batteries.
Can I simulate the Op-Amp Inverting Amplifier online for free?
Yes. The BitForBytes Embedded Lab solves the circuit in time, the way SPICE does (nodal analysis with real diode, transistor and capacitor models), and gives you a bench power supply, function generator, oscilloscope and multimeter to measure it — free, in the browser.
What does this circuit show?
A TL071 with Rin = 1 kΩ and Rf = 10 kΩ on ±9 V batteries. A 0.5 Vpp, 1 kHz sine comes out as 5 Vpp, upside down.
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