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.
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Clamp transistors in folded cascode for slew rate improvement
Razavi's textbook Design of Analog CMOS Integrated Circuits (2nd edition) includes a possible option of improving the slew rate of a folded-cascode amplifier in Figure 9.77, included below (along with ...
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How to achieve very slow slew rates in n-channel mosfets? [closed]
I am designing a DC load with 20 parallel power MOSFETs. Each to carry 3 A at most. So, the power dissipation will not be a problem. I am trying to achieve as slow as 1 mA/µs current slew rate and ...
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Effect of GBW and slew rate for "small signal"
I would like to better understand how to choose an op amp for high speed application and more precisely I would like to better understand how the GBW and the slew rate influence the transient response/...
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How to measure the slew rate of fully differential op-amp?
Shockingly simple question but for some reason I cannot get a configuration to work. I already designed a folded cascode op-amp and I can measure the slew rate using the Cadence function "...
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Can someone give an example of an op-amp whose positive and negative slew rates are different?
Can someone give an example of an operational amplifier whose positive and negative slew rates are different from each other? I have searched for it in the book Design of Analog CMOS Integrated ...
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Discerning slew rate and bandwidth limitations
What I get is that, considering a 2 stage OTA, we have 2 effects that limit the amplitude and frequency of the amplified signal:
Bandwidth of the amplifier: as the frequency of the input signal gets ...
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Are there any published values for GPIO slew rate or rise/fall times on ESP32?
Are there any published values for GPIO slew rate or rise/fall times on ESP32? I had a look at the datasheets and couldn't find any. I also couldn't find any measurements elsewhere. Have Espressif ...
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Ideal op-amp used as a digital buffer: rise time
Vo = Vin, so the rise time for both should be the same, but the capacitor takes some time charging.
How can I find the charging time without any other information here?
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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 ...
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Does slew rate specification of an op amp remain valid for an integrator configuration?
I am trying to design an op-amp integrator for a Rogowski Coil based current sensor. The op amp I use is THS4631D from Texas Instruments. It has a slew rate of 1000 V/us according to the datasheet. ...
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How to create an RS485-compatible line driver with an adjustable slew rate?
I need to make an RS485 compatible line driver, capable of 12Mbit/s with fast slew rate, but with the capability to reduce the slew rate to about 50ns rise/fall time when operating at lower bitrates.
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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 ...
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Rise time vs Slew Rate
I am using this device which is a LS1046. It list slew rate as 1V/ns to 4V/ns.
It is measured over a region of .35XOVDD to .65XOVDD where OVDD is 1.8V
So over the range of .63V to 1.17V which is .54V
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How to improve slew rate of LM741?
I am trying to implement a square wave generator with a specific output frequencies (15 - 45 kHz) but I've encountered a problem, the 0.5 V/μs slew rate. From what I've researched the main component ...
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Slew rate in a transmission line
Let's say I have a 3km long transmission line with a capacitance of C = 50pF/m, the resistance is 100Ohm. The inductance and the conductance per unit length are negligible.
If I want to receive the ...
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Op-amp speed: bandwidth vs slew rate
I was learning about the difference between op-amp slew rate and bandwidth.
Everywhere it says slew rate is a large signal parameter and bandwidth is a small signal parameter.
I have few questions:
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DIY function generator with an operational amplifier
I am trying to make my own function generator.
I will make it with adjustable frequency and peak voltage but for test reasons I'm simulating a constant frequency one.
My output has distortion which I ...
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What is the uncertainty of the Analog Discovery oscilloscope?
I'm an electrical engineering student and I have to measure the Slew Rate of an opamp (and most importantly its uncertainty).
I created a simple voltage follower circuit and I'm using the Analog ...
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Solid State Relay/High Voltage Switch unacceptable transient behavior
I am using a whole array of IXYS CPC7524 high-voltage switches in one of my designs. Although the design of this specific switch is not made explicit, its characteristics and other products in the ...
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Environment effect on slew rate of operational amplifier
Is there any environmental condition that will affect the slew rate of operational amplifier? I have been searching on it but there is no solid answer.
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Slew Rate Explanation
I'm currently studying the concept of slew rate and everything I read or watch I don't fully understand. I was hoping that someone could explain it like you were teaching a child. Another question I ...
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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'...
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Bandwidth vs slew rate
I have some difficulties in understanding the difference between bandwidth and slew rate.
I got that we are talking about large or small signal but what if for example the input signal is a PWM one ...
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How to calculate the rise time?
The figure shows a modification, from state A to state B, carried out on the cell at the output of circuit (X).
In both cases, the voltage at point A is the same. The transistors M1 and M2 keep the ...
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RS485 slew rate limiting remove need for termination
In regards to the highlighted feature of "slew-rate limiting" RS485 ICs. It says in multiple brand datasheets that the slew-rate limiting helps with transmission errors when there is ...
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Slow slew rate causes signal inversion, missed pulses
I’m currently revising a legacy design using an old Lattice MACH 5 PLD. One of the (TTL) inputs to the PLD has a slow slew rate on the rising edge, spending some 25ns between 0.8V and 2.0V, and the ...
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Op-Amp Unity Gain Frequency
I'm tasked with finding the unity gain frequency of an op-amp using the datasheet specs provided to me (just a homework exercise, not a real op-amp). There is no direct spec given for "Unity Gain ...
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What is currently the highest slew rate of any available op-amp? [closed]
Also, how is there a theoretical/practical upper limit to slew rates?
Suppose a customer wanted an extreme high speed op amp with a slew rate of, say, 5 Volts per femtosecond(which would translate to ...
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NE5532 slew rate
datasheet: http://www.ti.com/lit/ds/symlink/ne5532.pdf
I saw in most opAmps this rate was given as V/us, for example, for LM741 it was 0.5V/us. Is this 9V/ms a typing error? Because if it is not, then ...
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Finding Rise time and Fall time with Slew Rate Specification
I am using this QSPI Flash Memory IC
I'm operating the QSPI clock at 48MHz. I am probing the Clock and Data signals in my scope.
On Table 54 which is on Page 128, we have Rise time and fall time ...
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Question about charge and discharge of a capacitor
Let's consider the following amplifier:
and suppose that a capacitor is connected between the output node and ground.
Let's suppose that the inverting terminal becomes much larger than the non-...
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Question about the slew rate
Let's consider an op-amp:
From basic courses of electronics, we know that the output voltage as a function of the differential input is given by the following picture:
Now, assuming that:
the op-...
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CA3140 wideband output amplifier
The following circuit is nearly exactly what I need for the output stage of my function generator:
datasheet: https://www.renesas.com/us/en/www/doc/datasheet/ca3140-a.pdf
What I don't understand is ...
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Calculation of the slew rate of an inverter with active load
I'm studying the inverter with active load, whose scheme is the following:
Now, the author of my book says:
"We have to ensure a proper large-signal driving of the output node. The load of the ...
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Limit in-rush current for DCDC
We are using a Isolated Fixed-Ratio DC-DC Converter from Vicor (http://www.vicorpower.com/documents/datasheets/ds_BCM4414xG0F4440yzz.pdf)
that is powered through a 600VDC accumulator.
The DCDC powers ...
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Howland source for adjusting slew
I am using a Howland current source and sink in the above circuit for adjusting slew rate, however I am not getting desired results.
simulate this circuit – Schematic created using CircuitLab
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Inverting OP AMP SLEW RATE
I'm trying to do a question that requires me to design an inverting op-amp in multisim and find the slew rates in different scenarios using the OPAMP_5T_VIRTUAL operational amplifier model found in ...
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Communication between device for 5 meters and low speeds
I need to make a communication between only two devices with a distance of 5 meters, which are connected by a cable of 4x2.5mm² (see in the image), being 1 wire for GND and wire for 12v, that would ...
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Why is the slew rate in nMOS amplifiers worst when the output is going from low to high?
Likewise, why is the slew rate in pMOS amplifiers worst in the other case? (Output going from high to low.)
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Can an amplifier slew rate be used as a low pass anti-aliasing filter?
A slew rate calculator says that for an arbitrary 100MHz signal a minimum slew rate of 1884V/μS is required.
If I used an amplifier with that exact slew rate is it also a low pass filter? It seems ...
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Will the DC offset of signal affect the slew rate in an op amp?
I'm curious if the DC offset of a signal going into an op amp will affect the slew rate. Lets say you have an op amp configured to drive a 150 Ω load and is spec'ed to provided an output swing of ±3 ...
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Buffer requirements for S/H circuits
I am trying to solve question 11.10 which is taken from 2001 GATE IN paper.
So I think the answer is (a) because the input buffer which faces the analog input needs a higher slew rate in order to ...
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Slew Rate related EMI: How relevant is it for motor control circuits ?
I am designing a 3-phase inverter board for BLDC Motor control. The H-bridges i use are IFX007 from Infineon. The mentioned IC has the possibility to adjust the slew rate.
From what i have read, i've ...
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Operational amplifier for higher slew rate
what are the possible ways to improve slew rate of an operational amplifier in CMOS technology?
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H-Bridge Adjustable Slew Rate: Why is a decoupling capacitor needed?
I am designing a simple 3-phase inverter for BLDC Motor control. For that purpose, i plan to use a IFX007T from Infineon. The slew rate is controlled via a resistance connected in series to SR pin.
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Constant DC load stability and bandwidth slewrate
For this circuit, how do I know if the rise edge was limited by slew rate or bandwidth? What's the effect of R2 and C2 on bandwidth?
-3db of this circuit in simulation is 649 kHz, I know in this ...
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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).
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How do I decrease the slew rate of an op amp?
I need to reduce the slew rate of a voltage follower, so that if I change the input signal from 0 to 5V, the output signal will rise progressively up to 5V in say, about 5 seconds, so a slew rate of ...
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Slew Rate controlled MOSFET switch
This circuit controls the rate at which M1 switches on using the current mirror consisting of Q1 and Q2. A digital pot is used to control the current through Q2. The circuit works great in simulation, ...
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Question regarding slew-rate
I have a question regarding SR effect.
Let's say that we have some simple amplifier with op-amp with the following parameters:
\$G=+10 \ V/V, \ f_c=1MHz, \ SR =1V/\mu s, \ V_{supply}=\pm 15V\$
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