Questions tagged [transimpedance]
The transimpedance of a device relates the current through the input of the device to the voltage across the output of the device.
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How much variation in the transimpedance gain of the TIA is acceptable?
I have designed a transimpedance amplifier with a transimpedance gain that varies from 113.1dB to 111.46dB over a current input range from 200nA to 6uA. Is this variation in transimpedance gain ...
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Finding poles of the transimpedance amplifier
I`ve been having problems with finding poles of one transimpedance amplifier.
Acording to LTSpice the first pole should be somewhere around 1.6MHz, but I cant get that (I am getting about 200MHz). I ...
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Photodiode Circuit Output Saturating to 0V. Is there a way to salvage these boards?
My colleague and I recently designed and ordered a PCB intended to capture red laser light using a SFH2440 photodiode. We used the analog devices photodiode circuit design wizard to design the ...
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Sensitive Transimpedance Amplifier frequency bandwidth [closed]
I've built the transimpedance amplifier based on this project Sensitive Transimpedance Amplifier Oscillates. I've used op amp LMC6001, symmetrically power 5 volts, feedback resistor Rf = 100MΩ, ...
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Does TIA amplifier minimize the capacitance of a photodiode?
Let's say we have a photodiode modeled as follows where Cs represents PD capacitance:
We can say that, the larger the Cs the slower the response time of the photodiode.
Now we can use this photodiode ...
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Filter non-inverting input of operation amplifiers or directly to GND?
In the following configuration on this operation amplifier (OPA838), which is transimpedance configuration, can I connected the non-inverting input directly to GND, or should I use this filter?
Not ...
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Connecting an op-amp to a second-stage amplifier: loading effect considerations
I designed an amplifier with an OPA838 as follows:
First scenario: I want to connect the OPA838 to a next stage voltage LNA (Low Noise Amplifier).
What components or circuit should I add to my output ...
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Transimpedance amplifier oscillating at high gain setting on PCB only
I am trying to make a bare minimum transimpedance amplifier for a very large Si photodiode (Thorlabs FDS1010). My circuit is just like in the picture except my digipot is an AD5272-100kohm and my ...
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Transimpedance amplifier with OPA838 - instability
I have the following circuit as a transimpedance amplifier for ultrasound application:
I checked all the possible criteria for the stability of the circuit, including phase margin, step response ...
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How does this Precision, High-Speed Transimpedance Amplifier work?
I am confused by the equivalent circuit of the OPA380, a precision Transimpedance Amplifier from Texas Instruments. The internals of the amplifier are pictured below:
I assume the integrator and the ...
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Simulation of transimpedance amplifier in LTspice
I am trying to simulate a circuit that is presented in a research paper by Dr Behzad Razavi. I am using LTspice for the simulation (please see the attached image and netlist for the circuit).
I am ...
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How/why exactly does this JFET work as a current source?
I am designing a mic amplifier with a transimpedance amplifier circuit. The mic is connected to a JFET. I know how a transimpedance amplifier works and that it works by converting current into a ...
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High pass filter after TIA is not behaving as expected in LTspice
I have the following schematics to amplify a current signal modulated at 10 kHz. The first stage is a transimpedance amplifier with a -3dB bandwidth of 72 kHz. The second stage is a high pass filter ...
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Right transimpedence amplifier choice for input range
I have a device that produces a ±30 nA signal and I'd like to measure this to a 0.1 nA precision.
Since the currents are so low and I don't have much time to make mistakes, I am planning to use a TIA ...
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Putting a RC filter after the photo-diode to AC-couple the TIA gain stage
I have been designing a photo-diode circuit which separates out DC and AC signal of the photodiode. I am using MAX4007 as the current mirror for the DC branch and I am using OPA858 as the ...
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