Questions tagged [gain-bandwidth-product]
the product of the amplifier's bandwidth and the gain at which the bandwidth is measured.
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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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Maximum Gain For Chopper Stabilized Instrumentation Amp (MCP6N11)
I am using a Microchip MCP6N11 chopper stabilized instrumentation amplifier to amplify the signal from a MPX2300DT1 Wheatstone bridge pressure sensor. My schematic is attached. As shown the gain is ...
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gain of opamp circuit with current output
I'm designing a current source using a MOSFET driven by an opamp. The opamp controls the gate by comparing the voltage on a shunt resistor to the input reference. You could say that the fet replaces ...
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OPA211 weird frequency response --- why?
I'm using an OPA211 in differential mode with unity gain; no external compensation. I'm getting a puzzling ~10MHz bandwidth (specs indicate a bandwidth of 45MHz at G=1) with a peak at 8MHz (consistent ...
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Understanding of Dominant Pole Compensation
According to Miller Effect, within amplifying devices such as transistors that have inverting voltage gain higher that one, there should be increased input capacitance with increased voltage gain of ...
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Influence of NFB on the Gain of Amplifier
NFB is an acronym for negative feedback.
Lets say that we have an amplifier with three stages: input (differential) stage followed by voltage amplification stage and output power stage. And we have a ...
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OpAmp Design Questions for Transimpedance Amplifier
I'm trying to improve on a transimpedance amplifier design by changing out the op-amp that I'm currently using for another one. The issue I'm facing now is that I'm unsure as to how to pick a good op-...
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Finding the frequency of opamp to get a specific voltage gain
In the following question, they ask for the frequency at which the gain would be 1.41 V/V. The dc or low frequency closed loop gain is 2V/V (6 dB). Is the solution of the following question done ...
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Gain-Bandwidth of LTC6409
I am planning to use a differential amplifier, LTC6409 which is reported to have a GBW of 10GHz. I ran an AC analysis on LTSpice using the Spice model given here. I connected the negative input to ...
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Gain-bandwidth product proof for open loop/closed loop opamp
On the forum, post #12, Ghar claimed that the proof gain-bandwidth product from wikipedia is awful and he gave another proof but with feedback.
https://en.wikipedia.org/wiki/Gain%E2%80%...
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Parameters of a current sense amplifier
I am trying to select a current sense amplifier for my design. My design parameters are :-
Vrail:- 9V to 21V
ILoad :- 20A(max)
When I look on digikey,
http://www.digikey.com/product-search/en/...
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Bandwidth of inverting and non-inverting op-amps
If the same op-amp is used in both inverting and non-inverting modes (with same closed loop gain using appropriate resistors),
will the closed loop bandwidth of the op-amp in both cases be the same?
...
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Understanding Op-Amp gain bandwidth product
Below is the schmatics and AC transfer function for transimpedance amplifier from this design.
According to the datasheet, OpAmp has the gain bandwidth product of 20MHz.
But, here the gain is 94.58 ...
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