All Questions
Tagged with differential amplifier
160
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Are there fully differential feedback amplifiers with series inputs?
There are several examples of the 4 feedback topologies in single-ended circuits.
In the case of series inputs (i.e. series-shunt and series-series topologies), the input is connected directly to an ...
- 1,360
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102
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Differential amplifier, calculation of differential and common gain
Maybe someone can help and knows how to calculate the differential gain and common-mode gain in a differential amplifier.
Will the formula for differential gain be Ad=Rc/2Re, i.e. in my case 50/40=1....
- 11
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202
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Benefits of a differential PA in an RF power combiner design
Looking at the schematic for the Shure PA770 Antenna Combiner (found in their FCC listing) we can see the design is fairly straightforward, some amplification before combining via a typical Wilkinson ...
- 143
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282
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Paralleling opamps in a differential input first gain stage
I'm combining opamps to reduce the frontend opamp noise by a factor 0.707. This works in LTSpice, and I understand why it should work. My circuit amplifies a signal that is symmetric around 2.5V and ...
- 166
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52
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Best way to drive high speed ADC with differential inputs
Currently I am using AD8137 to convert my single ended signal to a differential signal. The ADC I am using is ADC3422 from TI and the data sheet suggests a passive circuit to drive low frequency ...
- 237
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What happens if you go below the minimum common mode voltage of a current sense amplifier?
This might be a simple one, but I can only seem to find information on going above the common mode voltage (VCM), not below it. Obviously going above the VCM upper limit will damage the device.
I'm ...
- 19
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45
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Differential and Common Mode Signals
if ı have amplifier and my ınput ac voltage and v is 2v haw can ı Guess and sketch output of common mode signal.
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answer
205
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How should the differential gain of an op-amp be interpreted?
Let us consider an open-loop op-amp circuit:
The output voltage including the common mode signal is given by:
$$
\mathbf{v}_{\mathbf{o}}=\mathbf{A}_{\mathbf{d}} \mathbf{v}_{\mathbf{d}}+\mathbf{A}_{\...
- 61
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160
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Single Ended Mode Amplifier Problem
There is an ac equivalent model of single ended mode - differential amplifier circuit. I don't understand how can be assumed to be Ib1 = Ib2. Even we don't have a voltage source on second input.
I ...
- 1
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3
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139
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Why are collector resistors grounded in AC small signal analysis of a differential amplifier?
Why are \$R_{C1}\$ and \$R_{C2}\$ grounded while doing small signal analysis?
4
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378
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Why don't I get the right values for Vout=Gain(v1-v2) for this differential BJT amplifier?
I am trying to use the formula that they have mentioned Vout=Gain(v1-v2), in my simulator I have placed one signal at 0.001V and the other one at 0V. The gain that they have found is 192, so I expect ...
- 227
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72
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Gmo2 from vout about differential amplificator
I'd like to know if this demostration is correct to calculate Gmo2 from vout about differential amplificator from this diagram :
1 : Gmo transconductance about Common Base configuration
2 : Gmo1 ...
- 99
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3
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438
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In a differential pair BJT amplifier, the individual gain of the transistors should be equal. Why am I getting different gain for each transistor? [closed]
Here I have taken a differential BJT pair. Both the individual gains are different and the output differential gain is also different.
Is there a problem with my circuit? Why is it happening?
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243
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What kind of amplifier do I need for differential to single-ended audio conversion?
This is a follow up to my previous question: For my Amazon Echo related project, I realized that the speakers in the Echo are being driven from a differential amplifier, and not a single ended one.
...
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148
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Why is input resistance parallel with the base of BJT?
I'm solving for the third stage. The resistance looking into the base of Q7 is taken between its base terminal and ground as follows during small signal analysis for single end gain of Second Stage ...
- 125