---
title: "Slew-rate distortion check, 470 kΩ/10 kΩ inverter"
subject: "Advanced Electronics"
chapter: 2
key: "semester_4/advanced_electronics:slew-rate-470k-10k"
source: https://www.bctengineer.com/q/semester_4/advanced_electronics/slew-rate-470k-10k
site: BCT Engineering
---

# Slew-rate distortion check, 470 kΩ/10 kΩ inverter

Advanced Electronics · Chapter 2: Operational Amplifier Characterization

- Asked in: 2073 Shrawan, 1+6 marks; 2073 Chaitra, 1+6 marks; 2069 Chaitra, 7 marks (asked 3 times)
- Video: [#172: Basics of Op Amp Gain Bandwidth Product and Slew Rate Limit](https://www.youtube.com/watch?v=UooUGC7tNRg) — w2aew
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_4/advanced_electronics/slew-rate-470k-10k
- Whole chapter: https://www.bctengineer.com/md/semester_4/advanced_electronics/chapter-2

## Question

Define slew rate of op amp. An inverting configuration op amp has feedback resistor 470 kΩ and input resistor 10 kΩ. If input signal is 0.1 sin(200000t) V, determine whether the output will be distorted due to slew rate limiting of op amp. If so, find remedy. The op amp has slew rate of 0.5 V/μs.

## Short answer

Slew rate is max dVo/dt. Gain = 470k/10k = 47, output peak = 4.7 V, required slope = 2×10⁵×4.7 = 0.94 V/µs > 0.5 V/µs, so output distorts. Use an op‑amp with SR ≥ 0.94 V/µs or reduce Rf to ≤ 250 kΩ (gain ≤ 25).

## Answer

#### Slew rate
**Slew rate (SR)** is the maximum rate of change of the output voltage of an op-amp, SR = (dVo/dt)max, in V/µs. It is limited by the current available to charge the internal compensation capacitor (SR = I/C).

#### Checking for distortion
Given: Rf = 470 kΩ, R1 = 10 kΩ, vin = 0.1 sin(200000t) V, SR = 0.5 V/µs.

```text
Closed-loop gain |Av| = Rf/R1 = 470/10 = 47
Output peak     Vm   = 47 × 0.1 = 4.7 V
Angular freq    ω    = 2 × 10⁵ rad/s
Frequency       f    = ω/2π = 31.83 kHz
vo = -4.7 sin(ωt)
Max slope of output = ω·Vm
   = 2 × 10⁵ × 4.7 = 0.94 × 10⁶ V/s = 0.94 V/µs
```

Required rate 0.94 V/µs > SR 0.5 V/µs, so **the output will be distorted** (the sine wave turns into a triangular-like wave of smaller amplitude).

Equivalently, the full-power bandwidth for 4.7 V peak is fmax = SR/(2πVm) = 0.5 × 10⁶/(2π × 4.7) = 16.93 kHz, which is below the signal frequency of 31.83 kHz.

#### Remedies
Any one of the following:

1. **Use an op-amp with higher slew rate:** SR ≥ 0.94 V/µs (e.g. LF351 with 13 V/µs).
2. **Reduce the gain:** the largest undistorted output peak is Vm = SR/ω = (0.5 × 10⁶)/(2 × 10⁵) = 2.5 V, so gain ≤ 2.5/0.1 = 25. With R1 = 10 kΩ, **Rf ≤ 250 kΩ**.
3. **Reduce the input amplitude:** for gain 47, Vin(peak) ≤ 2.5/47 = 0.0532 V (53.2 mV).
4. Reduce the signal frequency below 16.93 kHz (if the application allows).

**Answer: required 0.94 V/µs > 0.5 V/µs, so the output is distorted; use Rf ≤ 250 kΩ or an op-amp with SR ≥ 0.94 V/µs.**

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is slew rate?
   A. Maximum rate of change of output voltage, SR = I/C
   B. The gain bandwidth product
   C. The input offset
   D. The CMRR
   Answer: A. It is limited by the current charging the compensation capacitor. (Key point: Definition)

2. What is the output peak for Rf = 470 kΩ, R1 = 10 kΩ and 0.1 V input?
   A. 0.1 V
   B. 47 V
   C. 0.47 V
   D. 4.7 V
   Answer: D. Gain 47, so Vm = 47 × 0.1 = 4.7 V. (Key point: Output peak)

3. Is the output distorted?
   A. No, 0.94 V/µs is below 0.5 V/µs
   B. Yes, because gain is below 1
   C. No, because f is low
   D. Yes, required 0.94 V/µs exceeds SR 0.5 V/µs
   Answer: D. Max slope ω Vm = 2×10^5 × 4.7 = 0.94 V/µs > 0.5 V/µs. (Key point: Distortion)

4. What maximum Rf avoids distortion with R1 = 10 kΩ?
   A. 25 kΩ
   B. 250 kΩ
   C. 100 kΩ
   D. 470 kΩ
   Answer: B. Vm ≤ SR/ω = 2.5 V, gain ≤ 25, so Rf ≤ 250 kΩ. (Key point: Remedy)

## Related in Advanced Electronics

- [Slew-rate distortion check, 330 kΩ/10 kΩ inverter](https://www.bctengineer.com/question.md?key=semester_4%2Fadvanced_electronics%3Aslew-rate-330k-10k) — Advanced Electronics, chapter 2
- [Slew-rate check for four input signals](https://www.bctengineer.com/question.md?key=semester_4%2Fadvanced_electronics%3Aslew-rate-multiple-signals) — Advanced Electronics, chapter 2
- [Slew-rate check for 40 dB amplifier at 20 kHz](https://www.bctengineer.com/question.md?key=semester_4%2Fadvanced_electronics%3Aslew-rate-40db-20khz) — Advanced Electronics, chapter 2
- [Input impedance of inverting op-amp](https://www.bctengineer.com/question.md?key=semester_4%2Fadvanced_electronics%3Ainverting-input-impedance) — Advanced Electronics, chapter 2
- [Voltage follower square-wave output with slew rate](https://www.bctengineer.com/question.md?key=semester_4%2Fadvanced_electronics%3Avoltage-follower-square-wave) — Advanced Electronics, chapter 2
- [Output voltage of two op-amp IA](https://www.bctengineer.com/question.md?key=semester_4%2Fadvanced_electronics%3Atwo-opamp-ia-output) — Advanced Electronics, chapter 4

## Related in other subjects

- [Transfer function of op-amp with Rs ∥ C feedback](https://www.bctengineer.com/question.md?key=semester_3%2Fcontrol_systems%3Atf-opamp-rs-c-r1-r2) — Control Systems, chapter 2
- [Non-inverting op-amp voltage gain](https://www.bctengineer.com/question.md?key=semester_1%2Ffundamental_of_electrical_and_electronics_engineering%3Anon-inverting-amplifier-gain) — Fundamental of Electrical and Electronics Engineering, chapter 6
- [Ideal op-amp properties; non-inverting gain](https://www.bctengineer.com/question.md?key=semester_2%2Fbasic_electronics_engineering%3Aopamp-props-noninverting-gain) — Basic Electronics Engineering, chapter 4, asked 3×
- [Ideal op-amp properties; inverting gain](https://www.bctengineer.com/question.md?key=semester_2%2Fbasic_electronics_engineering%3Aopamp-props-inverting-gain) — Basic Electronics Engineering, chapter 4, asked 3×