All Questions
Tagged with differential instrumentation-amplifier
21
questions
0
votes
1
answer
156
views
Function generator cannot generate differential voltage?
I am using the AD620 as instrumentation amplifier to amplify the body's ECG signal. An ECG is a differential signal (measured with two electrodes) and I want a differential gain of \$G_d = 1000\$.
The ...
- 4,145
0
votes
0
answers
253
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Oscilloscope "isolated" inputs
As I don't want to see my oscilloscope go up in flames when I play with probing circuits, I was wondering the following:
First off, my goal is to measure different floating voltages aka the "GND&...
- 47
9
votes
6
answers
2k
views
Do you have to use an instrumentation amplifier to measure voltage across a 0.01 ohm shunt?
I was planning on implementing a current sense feature on the STM32 Bluepill to measure the current output of a solar panel (150 mA short-circuit current, 14 V Open-circuit voltage) using LM358 ...
- 633
1
vote
0
answers
387
views
Differential integrator vs standard
I want to integrate/amplify a very small signal (relatively short pulses of 100ns to 4ms, necessitate high-bandwidth components minimum 40MHz+). The capacitors will be switched (shorted) when not in ...
- 469
0
votes
1
answer
79
views
Best way to combine different frequency sinusoids to simulate noise?
I'm designing a differential amplifier to remove noise from a signal, and I'm trying to verify my design by simulating a noisy input, but I'm not sure how to do this. The diagram below is roughly what ...
- 157
0
votes
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28
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Switched-cap/charge pump only way to generate negative rail voltage for op-amp?
I need to design a daughterboard that gets mounted directly to a piezo mic to condition the signal before transmission. Part of the conditioning is a full wave rectification.
Thus, as you'd expect ...
- 201
0
votes
1
answer
749
views
Measuring current, instrumentation or differential amplifier?
I want to measure current at the high side of circuit with 0.1 mV accuracy using a 16 bit ADC. for sensing the voltage drop over a 100 mΩ 1% resistor I need to use an op amp which is cheap and easy to ...
- 2,396
0
votes
1
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1k
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Differential RC filter
I sometimes see differential filters like this:
And sometimes this :
Basically sometimes there are 3 caps (2 going to ground on each input), sometimes I only see 1 cap ( 1 differential cap, none ...
- 469
0
votes
2
answers
164
views
Noise mitigation in +/-5mV instrumentation amplifier?
I am building a differential amplifier to boost a 0-5mV (delta) signal off a load cell wheatstone bridge.
In simulation, the design works here (falstad):
(for those who have not used falstad circuit ...
- 201
0
votes
2
answers
180
views
Mathematical model for differential signals and relation with reality
i have a question and i hope is not that strange.
i spend some time asking myself how people came out with the mathematical model for differential signals and why is this better in this way?!
to be ...
0
votes
1
answer
223
views
Effects of increasing current on external noise and SNR for analog transmission
This is a conceptual question about long analog signal transmission exposed to capacitive coupling and EMI noise as shown in below figures:
simulate this circuit – Schematic created using ...
- 12.2k
0
votes
1
answer
303
views
Effect of bias resistor value on common-mode rejection in a differential or instrumentation amplifier
In the below schematics a source is coupled to a differential amplifier.
Rb is a bias resistor for bias currents to flow:
Since in instrumentation amplifiers it is a remedy to add resistors for bias ...
- 4,333
0
votes
1
answer
156
views
How do non-flowing common mode or bias currents cause common mode range to exceed/float?
Below is a very simplistic view of differential ended inputs of a data-acquisition channel's inAmp which measures a floating battery voltage V. To make concepts and explanations simpler I use two ...
- 4,333
3
votes
1
answer
1k
views
Instrumentation amplifier noise amplified
I built a simple circuit with an instrumentation amplifier (PGA204AP) in order to clean a differential signal from noise. The signal is generated few meters away from the acquiring point and the cable ...
- 382
5
votes
2
answers
11k
views
Differential to single ended circuit
I have a differential signal up to 1.5 MHz and have to transform it to a single ended signal.
I have found this amplifier which has a BW of 2.2 MHz and should therefore be okay for this task.
The ...
- 93