Questions tagged [differential-amplifier]
For questions about circuits that amplify the difference between two input signals but not the signal common to the two inputs (e.g. the long-tailed pair). Do not use for questions about operational amplifiers (which are a type of difference amplifier) unless the op amp is used as a differential amplifier -- use only the "operational-amplifier" tag for most questions about op amps (e.g. an op amp as an inverting amplifier).
314
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Confusion with two types of differential signal coupling
I'm having difficulty to articulate the question. But perhaps I might get close to it by an example.
I know that in differential signaling, both the signal and the receiving amplifier can be in ...
- 4,333
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30
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MOS differential amplifier output swing
Why is the maximum output voltage swing of a MOS differential amplifier 2Vdd-4Vdsat? I understand that the voltage swing of a MOS CS amplifier, but I don't know how they got that the voltage swing of ...
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Working of differential pair using MOSFETs
I am currently learning about differential pair using MOSFET from this course. In this particular lecture, the teacher says that to have a differential pair we need to apply the second signal v2 at ...
- 180
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1
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Common-mode choke in ECG circuit
I'm designing a PCB for single lead ECG measurement and I ran across this TI reference design that contains a common-mode choke (P/N Murata DLW31SN900SQ2L). What's strange is that I can't find any ...
- 137
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AD8232/AD8233 not working for sEMG
I am working on an sEMG circuit using the AD8232 and cannot figure out what is going wrong, the circuit isn't outputting the correct signal when connected to the forearm. I am using the 3 lead ...
- 11
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Is it safe to flip the use of resistor pins of the INA106 differential amplifier to turns its gain from 10 into 0.1?
I'd like to have differential amplifier with gain of 0.1 without having to put any external resistor. Most of them in the datasheet states the use of gain of 1 or more and rarely specify the use of ...
- 834
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2
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Differential amplifier Q point
I'm looking for a way to solve the Q point of this amplifier
I found this set of equation :
EQ1: I=Ic3(1+1/Beta3)+Ic4(1+1/Beta4)
EQ2: Ic1/Beta1+Ic2/Beta2=Ic4-Ic2
EQ3: Iout=Ic3-Ic1
EQ4: Ic1(1+1/Beta1)*...
- 59
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4
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Can differential probes be used with floating oscilloscopes, such as handheld/tablet scopes?
I am in the market for a differential probe (and possibly a handheld oscilloscope down the track for field work). One seller I came across has a warning for many of the probes that they sell saying &...
- 315
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1
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Distortion in a negative channel of the differential amplifier THS4505
I designed a single-ended to differential signal amplifier using a tool provided by Texas Instruments:
The source signal passes through a voltage follower (OPA810IDBVR), so the output resistance ...
- 75
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0
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54
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differential gain for mismatched \$g_m\$ in differential amplifiers
I couldn't understand how the author came up with the expression of differential mode gain. He states to look from the Fig 4.17 to derive this expression, whereas the fig 4.17 has no mention of \$R_{...
- 13
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Gain bandwidth calculation of two stage op-amp
I want to design a two stage single ended OTA without using a Miller compensation capacitance.
Every source that I have examined gives a design example with a compensation capacitance.
Hence, they ...
- 175
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1
answer
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Differential Amplifier Output Ringing
I designed this circuit. It is a fully differential amplifier of gain one. I am getting this ringing and noise on the output of tx1_o
Blue is where the probe is and ground is on circuit's ground.
Here ...
- 11
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2
answers
68
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How can i obtain a positive Vref for this circuit?
I have to design a irrigation system that uses a resistive moisture sensor to maintain a certain level of relative soil humidity for a plant. In order to convert the resistance changes of the moisture ...
- 41
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Differential input resistance of non-symmetric circuits
In Sedra and Smith (7th edition, section 2.4.1) when building up to an instrumentation amplifier there is discussion of how to use a single op-amp (differential input, single-ended output) to ...
- 675
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1
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Why does my common mode test still have tiny retained sine wave?
I used this equipment the BMA-200 with the AMP01 having a CMRR of 125dB.
I connected the signal generator output to both the In+ and In-. Yet the waveform still have retained sine wave of very small ...
- 847