Questions tagged [instrumentation-amplifier]
An instrumentation amplifier (InAmp) is an integrated circuit or operational amplifier topology that has high input impedance differential inputs and a low impedance single-sided output. Because of precision laser-trimming techniques for passive circuit elements, InAmps implemented as integrated circuits can achieve impressive common mode rejection ratios, while discrete OpAmp implementations can be disappointing in this regard.
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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 ...
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Instrumentation amplifier input bias currents direction and error
I am trying to understand how the input bias currents flow in op amp and instrumentation amplifier circuits and what errors they create. I came across a circuit that looks like the following:
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Wiring of INA128 instrumentation amplifier to Wheatstone bridge
Is there any issue with the wiring or calculations of my INA128 instrumentation amplifier to my load cell Wheatstone bridge? Currently I see no change in the output when connected to the oscilloscope. ...
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Removing DC offset from AD8220 output (Instrumentation Amplifier) in electromagnetic application
I'm using AD8220 to amplifying a very tiny signal, which is made by a electrode in a electromagnetic flow meter. In the voltage that is made by the electrode there is an DC offset, then this DC offset ...
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Instrumentation amp output not matching voltage drop in LTspice
I am trying to sample the voltage drop across different components at high frequencies, and figured the best way to do it was with an instrumentation amp so there's not much additional load placed on ...
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What voltage comes from a standard 6.3 mm instrument cable?
I am designing an electric percussion instrument using various metal strings and objects that are hit my solenoids. Pickups record the sound.I need to know what kind of voltage and current instrument ...
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Power supply issue with virtual ground for the INA333 and AD630 amplifier
I implemented a circuit with the INA333 amplifier to read a sensor, then the amplifier sends the signal to the AD630, which plays the role of a lock in amplifier, as in the diagram I sent.
I made a ...
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INA125 Reference Voltage lower than expected
I am using a INA125 to amplify the signal from a load cell. When I connect everything according to the datasheet as seen below, the reference voltage drops when I connect the load cell. I am supplying ...
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high voltage moderate frequency galvanically isolated current measurement
Given a conductor carrying a sawtooth wave of anywhere between 0.1Hz and 855kHz up to +-1.5kV) and anywhere between +-(1µA...20A)(maximum 650W) i want to measure the current with about 5MS/s (so the ...
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Noises from Sequential Bipolar Montage
If Fp1 and F3 forms a differential V+, V- and
F3 and C3 forms another differential V+, V- and
C3 and P3 forms another differential V+, and V- and
P3 and O1 forms another differential V+, and V-
What ...
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Noises when unused inputs not shorted with common V-
Update. Manufacturer confirmed all the 4 red V+ inputs used same blue V- and ground. Now what would be the noises introduced if only channel 1 is used and the 3 other inputs are floating (all ...
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What is the purpose of the "REF" pin of LTC6915?
I am working with a LTC6915 and i don't understand what REF pin does.
That like V+ - V- + Vref = Vout?
Or something else? I don't understand the datasheet.
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How to share a single gain resistor among multiple op-amps in a circuit
I'm currently designing a circuit where I need to implement multiple op-amps, each configured with the same variable gain resistor using a single digital potentiometer.
To simplify the design and ...
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Noises are measured over a bandwidth. Is 50Hz and 900Hz noise the same at 1kHz bandwidth? [closed]
They say noise is over a bandwidth. At a bandwidth of 1000Hz. Is the noise at 50Hz and 900Hz similar? If yes. Please made a quick drawing how the noise at 50Hz and 900Hz look like roughly so I can ...
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Single supply positive-only signal amplification using INA126 (two op-amp in-amp)
I need to amplify a 0.15-0.8 V very low frequency signal to the 0-10 V range of an ADC. I'm having a hard time figuring out why an INA126 does work as expected with dual supply but seems not to work ...
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