Questions tagged [gain-bandwidth-product]
the product of the amplifier's bandwidth and the gain at which the bandwidth is measured.
62 questions
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Op amp GBW compensation when used in MFB filter
I've been reading through this app note by TI where its proposed that when using a MFB filter a compensation resistor can be added to overcome limitations of lower GBW op amps. I've been working ...
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Bandwidth measured is two orders of magntiude less than expected TIA circuit
I have the following photodiode schematic, all soldered onto a small PCB. The first stage is a TIA, and the second stage filters out high frequency signals. The calculated bandwidth of the circuit ...
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Sensitive Transimpedance Amplifier frequency bandwidth [closed]
I've built the transimpedance amplifier based on this project Sensitive Transimpedance Amplifier Oscillates. I've used op amp LMC6001, symmetrically power 5 volts, feedback resistor Rf = 100MΩ, ...
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MDAC AC reference input
I previously had a question on using AC reference voltage with a MDAC, But it has been addressed nicely in the answer below.
How does the "Multiplying Bandwidth" specification relate to a ...
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I'm trying to design a CE BJT amplifier with 260 gain and Bandwidth of 5.5Mhz
I'm struggling to design a common-emitter BJT amplifier for my college project.
for this i selected a BC547 transistor and I have done the calculations by Assuming my Vcc as 12V. then I took Vce = 5V ...
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Generate a fast, high amplitude pulse for measuring slew rate
I need to create a test set-up that measures slew rate of a few op-amps. The fastest slew rate among all of the op-amps in my list, belongs to NE5532 with 9 V/us slew rate and output amplitude of ±10 ...
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OpAmp on Multisim keep amplifying over Gain Bandwidth Product
I have below circuit on Multisim with Current source replicating Photodiode and opAmp amplify current. However opAmp keep amplifying even at very high frequencies without considering Gain Bandwidth ...
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3
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Superimposing AC signal and DC signal
I am trying to add a sinusoidal signal to the positive and negative rails of an op-amp under test, and change the frequency and amplitude of this sine wave to test the CMRR and PSRR. I need to ...
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op-amp bias current measurement
I am trying to measure the offset voltage and bias current using the technique below (Figure 2 and Figure 3)
op-amp servo-loop
My question is: can I use NJM4580 as the op-amp under test and use the op-...
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How does the "Multiplying Bandwidth" specification relate to a DAC output's maximum bandwidth
I'm struggling to understand what it means for a DAC to have a Multiplying Bandwidth of 200kHz. Does it mean that the max frequency component in the DAC's output cannot exceed 200kHz for reliable ...
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Transit vs Unity Gain Frequency of a MOSFET
As far as I understand, the unity gain frequency of a transistor is its gain-bandwidth product, and the transit frequency of a transistor is a measure of how fast it is.
I've also read that the ...
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Opamp GBW is not matching with measurement
I have circuit below on breadboard with LF351N op-amp in transimpedance mode with feedback resistor of 10 kohm and 10 pF capacitor attached in parallel.
In datasheet of LF351N (Datasheet) it is ...
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Ways to get around amplification limited by op amp GBW?
I'm working on a project that requires me to amplify 70 pA to read out at 10 V (the digitizer I'm using to collect data has a range of 0 to 10 V readout). On top of this, I need to sample my voltage ...
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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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Slew rate, bandwidth and settling time
I have a system which has to be as fast as possible. The system has to sense a current across a shunt.
My first idea as I have no experience on this subject would be to take a "current sense ...
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How does the GBW of an op-amp affect the position of the passband cut-off frequency in a low-pass filter?
Let's say I have a 2nd order low-pass filter in a Sallen-Key configuration (Chebyshev), and the cutoff frequency should be the frequency at which the phase shift becomes -90°, how will the GBW (gain ...
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What chip has gain of 1000, bandwidth of 500 kHz? [closed]
I'm building a project that needs gain of 1000 (from mV) and bandwidth of 500 kHz. Is there an op-amp (or other parts) with this characteristic? Or maybe it is available in only very expensive parts (...
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Op-amp simulation
I am not sure what's the mistake I am making in the below simulation.
Below is an MCP660 non-inverting op-amp with a gain of 3.
Case1:
Input: 1 MHz;
Offset: 0.5 V;
Pk-pk amplitude: 0.2 V
Result:
The ...
user220456
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Lux meter 50 Hz sine noise filter
I've built the circuit with diagram:
I used R1 10 MΩ instead of 50 kΩ to get a higher gain. I wanted to measure light intensity, so I'm interested in DC output ...
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Two stage operation amplifier using MOSFET: How to increase the cut off frequency
so I'm trying to design a two stage MOSFET op amp and I'm required to get a gain bandwidth of more than 260Ghz. I'm biasing the first stage with Vb1 around 2.1 V, 1.9 for 2 and 2V for Vb3. With Vdd =3....
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Stable 94 dB gain op-amp amplifier
I would appreciate suggestions or best practices for designing a stable amplifier. My goal is to design a 94 dB gain low-noise op-amp amplifier for a 100 kHz signal with a bandwidth of 10kHz.
At this ...
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Design methodology for non-inverting summing op-amp
I'm trying to design an op-amp circuit to sum up four voltages by using a non-inverting summing configuration. You can see it in the circuit below, though for illustration's sake, the resistor values ...
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What is the upper frequency limit for an op-amp integrator?
I'm designing a circuit to process a di/dt signal. As the input is the differential of the measured current, I have to integrate the voltage to provide a representation of the current. The duration of ...
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Input Source Capacitance Value for GBW Calculation
For the calculation of GBW product for a photodiode:
Which diode capacitance value do I use for the input source capacitance (Cs)? I am having trouble understanding the difference between the 400pF ...
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Building a band-pass filter using an op-amp
I am quite new to op-amps but have looked at them in college and have done my own research on them. I am trying to use an op-amp to build a simple band-pass filter which has an in-band voltage gain of ...
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Why is the noise gain these opamps 500? I feel it should be 250
I wanted to check the bandwidth of the first stage of an instrumentation amplifier configuration and this is the circuit:
Since, the noise gain of an opamp is (1+Rf/R1), for each of the op-amps the ...
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Is -3dB bandwidth defined for any type of transfer function?
If I have response like the following, is it still valid to say bandwidth of the circuit is 2.31kHz?
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How much gain/bandwidth can I practically get out of the OPA1692?
I've built an Electret Microphone preamp based on this application note from the OPA1692 datasheet (page 27):
The circuit seems to work fantastic, but I've realized that I'd ideally need a bit more ...
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Constancy of gain bandwidth product for amplifiers
I've seen the assumption of gain-bandwidth product being constant for some amplifiers. More specifically for a compensated op-amp.
Is there any mathematical proof to establish why the product is ...
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Calculating the cut-off frequency
I have an inverter opamp with the next data :
\$A=-25\$
\$A_{ol}=20\frac{mV}{V}\$
Unity Gain Bandwith\$=10^{6}\$
Then asks for the cutt off frequency, so the open loop its passed to db
\$20\,\frac{V}...
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Constant Gain-Bandwidth product in amplifiers
Can somebody explain to me how the gain-bandwidth product is constant in an amplifier or op-amp? I want to know the mathematical expression behind it if possible.
As said here: https://en.wikipedia....
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Why do 2 different online active filter calculators give way different GBW requirements for the same frequency range?
I am confused about 2 different online active filter calculators giving different GBW requirements for the same frequency range. One calculator is giving GBW requirements in the kHz range while the ...
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Op amp advertised as BW = 105MHz, but GBP is actually 70MHz, what's being spec'd differently?
I just came about an op-amp spec where they say, "the Op-amp X is unity-gain stable with a small-signal unity gain bandwidth of 105MHz.." As you continue to read, it then says, "with a ...
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Cascaded Non Inverting Amplifier
I'm working on a project that requires at least 40 dB gain at 40kHz. I originally used one non-inverting amp using 10k and 1k resistors for a gain of 11. Using cascading rules for linear systems, I ...
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Did I interpret these multisim results correctly?
From the circuit above, this is what I have to do: " Connect the circuit with R3 equal to 470 kΩ. Set the input frequency to 100 Hz. Adjust the signal level to get an output of 5 Vp-p. Record ...
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Opamp: Compensate to achieve constant gain
I have been trying to achieve a constant gain across an LM318 opamp in a differential amplifier configuration ranging from 500Hz to about 500kHz.
The opamp has a bandwidth of 15Mhz.
Since the gain is ...
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Higher cutoff frequency of op-amp circuit is different in simulation and on paper
I have the circuit below:
This is an inverting amplifier, the op-amp that is used is 741 as shown in the circuit. Open-loop gain of the op-amp is \$ A_{0}=2\times 10^5 \$ and the cutoff frequency of ...
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Bandwidth of pentode amplifier
Why is the bandwidth of pentode amplifier larger than the bandwidth of triode amplifier?
I have searched the following books but can't find the answer:
Electronics devices and circuits by Rajiv ...
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How to amplfy µA from a fast photodiode with a bandwith of 10GHz
I want to measure faint laserpulses with a step slope (Bandwidth 5-10GHz). I have a photodiode which produces a photocurrent of some µA. Now I need a transimpedance amplifier to convert it to at least ...
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Gain bandwidth product for amplifier
If a question simply asked "What is the gain bandwidth product of this amplifier?"
And when I am trying to utilize the equation :
GBW = (Av)(BW)
I am unsure if I should utilize the voltage gain ...
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op amp design for bandgap
What values of the main parameters of an op amp are suitable in a bandgap reference design? The purpose is to obtain a smaller temperature drift in the range -40 to 125 C.
The model I am using now is ...
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What did my professor mean with this: gain-bandwidth product
After trying to ask multiple times my professor what he meant with this I still don't get it.
Basically I have an inverting amplifier with a specified gain-bandwidth product of 0.6 MHz.
Now as I ...
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MATLAB model of an op-amp's Open Loop Gain
I'm using MATLAB to analyze an amplifier in a transimpedance circuit, and I'm a little lost in implementing the op amp's open-loop gain function with the following formula:
$$A(s) = A_{OL} \cdot \...
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Finding a gain bandwidth product using a test frequency
For GBP datasheet parameters of Op-amps, I have seen datasheets with test conditions like gain and Rl, but there are also datasheets with ftest as their conditions. How do we calculate the GBP of the ...
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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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What's the largest practical stable gain possible?
I have a feedback application to set the voltage of a node in which there is considerable loss in the loop. Simulations tell me that a differential voltage gain of 10000, 80dB (roughly about what you ...
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What does the condition "f=100Hz" mean for the Gain Bandwidth Product?
In the LT6003 datasheet you can find the following information:
How do I read the Gain Bandwidth Product? I mean there is a typical bandwidth of 2kHz under the condition of f=100Hz and I'm not sure ...
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Gain bandwidth product of amplifier in a DC scenario
I think I have a simple (but still to me confusing) question regarding the gain bandwidth product (GBP) of an instrumentation amplifier: Datasheet (AD8237)
I have sensors that change their output ...
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Why Gain-Bandwidth Product of devices having a simple one-pole frequency response is constant?
I was reading wikipedia page of Gain-Bandwidth Product and got struck at one particular statement.
For devices such as operational amplifiers that are designed to have a simple one-pole frequency ...
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Wrongly documented TI LM324 unity-gain bandwidth?
I was reading the datasheet of the LM324 from TI (http://www.ti.com/lit/ds/symlink/lm324.pdf).
They specify a generic GBW of 1.2MHz. This is usually done with no output applied, from what I ...
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