Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [slew-rate]

Anything related to slew rate (SR in datasheets), i.e. a characteristic parameter of analog amplifier circuits (notably operational amplifiers). The slew rate of an amplifier is the maximum rate of variation that the input signal can exhibit in order for the output amplified signal to follow it without distortion.

Anything related to slew rate (SR in datasheets), i.e. a characteristic parameter of analog amplifier circuits (notably operational amplifiers and other integrated amplifiers).

The slew rate of an amplifier is the maximum rate of variation that the input signal can exhibit in order for the output amplified signal to follow it without distortion.

The S.I. unit for the slew rate is V/s, but more commonly its V/μs subunit is used (assuming the input signal is a voltage signal).

See also Wikipedia on slew rate.

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Why is it called "slew rate"?

For curiosity reasons, I want to know why engineers used the term "slew rate" for this op-amp phenomenon, I mean "slew". I googled it and found this: "turn or slide violently or uncontrollably". What is the explanation?
Zineddine Haboussi
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LM358 measured slew rate much higher than spec

I am measuring the slew rate of an LM358 op amp running +/-15V using both unity-gain (+/- 10V input signal = 2/3 full scale) and 'comparator mode' (+/- 1V input to noninv input, inv input grounded). I've made the measurement in situ as well, with a…
Sam Gallagher
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How the slew-rate and drive strength affect the output signal of the FPGA?

Can someone describe the difference between the drive strength and the slew-rate preferences in Lattice FPGA?
ercegovac
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Amplifying a PWM signal with an op amp. Is the slew rate a problem?

I need to amplify a PWM signal from 5V to 24V in order to drive a mosfet that in turn drives a small DC motor. The input signal has a frequency of 500Hz and comes from Arduino uno (pin 9). For amplifying the signal I thought of using a typical non…
mickkk
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Why is opamp slew rate specified at unity gain?

Is there some reason besides convention to add the "at unity gain" qualifier? Does adding or omitting it communicate something about the component? Are the opamps which have a slew rate that varies with gain?
Frosty
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Optimizing op-amp overload recovery behaviour

I'm measuring a thermocouple which connected series with a heating element. Heater is driven with PWM and when PWM is off-duty, a measurement is taken through output A0 using an ADC. Relevant parts of the circuit can be seen below. I think it is a…
sabbath
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Why does the op amp output in this circuit have low slew rate?

I have the following circuit on a bread board (with the exception of using AD820 instead of AD822 - the main difference based on the datasheets seemed to be one versus two op amps in one package). simulate this circuit – Schematic created using…
Mikko Rantanen
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If there exists a cascade of op amps, does the previous op amp's slew rate affect the later op amp's slew rates?

All op amps used are the same Texas Instrument LM348n. The datasheet says the op amp has a nominal slew rate of 0.5 V/µs, but gives no tolerance. I have a square signal with an amplitude of 500 mV peak to peak being sent into a two op amps system.…
Jonathan Riley
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Calculating Slew Rate from a time-constant

I have to choose an op amp mainly based on slew rate. I am using the op amp as a differential comparator with dynamic (time) hysteresis with a time-constant \$3\tau=500\mu\text{s}\$. My upper threshold of the hysteresis \$|U_{\text{th}}|= \pm…
atkristin
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How is the slope of the frequency response of an analog active filter defined?

I have seen different types of filters, and different slope values at -20 db, -40, etc. The literature says that the order define the slope, but how? How can it be mathematically justified? For example, I have a transfer function with a simple real…
avelardo
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Differential input voltage necessary for maximum slew rate in operational amplifiers

Today I ran into a problem with op-amp slew rate when playing with a design where an op-amp spends a lot of time in saturation, only to occasionally "come down" and regulate the output. (I'm simulating this using LTspice, and the op-amps are…
pipe
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Are slew rate frequency and cut off frequency same?

I am bit confused about the cut off frequency and the max frequency above which the output response starts to distort which is slew rate frequency. Are these two things same? Cutoff frequency (f) = GBP / Av Slew Rate Frequency (f) = SR/(2*pi*Vp) Is…
Dhiraj Dhakal
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Improving RS485 / UART slew rates

I'm trying to implement a half-duplex 1Mbps RS485 bus (1 master controlling ~8 motors). After facing occasional communication errors I've invested in a Saleae logic 4. The RS485 A/B lines probed directly give this output. (that framing error at the…
Avik De
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Is it good to have a higher slew rate? What are some of the effects due to slew rate limitations?

This question is in relation to the working of an op-amp. I know what slew rate is, but I am not entirely sure whether is it good to have a high slew rate. As far as my understanding goes, a higher slew rate should allow the op-amp to give the…
sangam.saga
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Slew Rate Calculation

I’m in the process of selecting an op-amp to act as a voltage follower for the input signal into my data acquisition card. I'm measuring all types of signals just like an oscilloscope would. Do I have the slew rate I need correct? I used this…
bigshop
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