Questions tagged [transconductance-amplifier]

A transconductance amplifier is an amplifier that takes a voltage as input and supplies a current as output.

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What are the loop gain and the transfer function of this transconductance amplifier feedback circuit?

Related to my previous questions, I would like to know what the approach for determining the loop gain and transfer function of the circuit presented below is: The circuit is highly simplified. The ...
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Would this be an acceptable implementation of an OTA-based voltage regulator?

I am building a discrete voltage regulator, centered on a differential pair with an active load. I have seen the single stage differential pair being called an Operational Transconductance Amplifier. ...
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Fully Differential OTA

Based on the figure below, could you explain how a differential ota works ? how can I get the transfert function if I want to set a pole or a zero at the output with a differential resistor and a ...
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Asymmetric Op-Amp Output - Transconductance Amplifier

I'll preface this post by saying I am a power engineer working in the utility world and my electronics knowledge is very rusty. The last time I worked with electronics was back in undergrad (~6 years ...
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LM13700 does not completely reduce the sound

I have a problem with LM13700 - it does not completely reduce the sound when the control current is zero. For testing, I put together the most basic circuit, where the control pin is connected to the ...
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Voltage controlled amplifier with single supply

I'm trying to make a voltage controlled amplifier circuit to control the feedback level of a delay effect. My big problem is that the circuit must be powered by a single power supply. I seem to have ...
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Discerning slew rate and bandwidth limitations

What I get is that, considering a 2 stage OTA, we have 2 effects that limit the amplitude and frequency of the amplified signal: Bandwidth of the amplifier: as the frequency of the input signal gets ...
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Can I use a resistor to transfer voltage to current rather using transconductance amplifier?

The situation is I intend to transfer voltage to current to control a laser. The voltage comes from an optical phase-locked loop (OPLL). It is changing over time, so the current transferred from this ...
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MOSFET - Frequency response

I tried to do an exercise from my textbook where I have to discover the gain for mid frequencies of the MOSFET below, but I can't solve it. I got stuck at one point. I drew the small signal ...
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Basic transistor transconductance amplifier - negative current gain?

I'm working through The Art of Electronics. In chapter 2, it breaks a common-emitter amplifier into two stages: a transconductance stage and a resistive load stage (or transresistance amplifier). ...
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Can't compute the value of Resistance of Operational Transconductance Amplifier [duplicate]

I have the following Operational Transconductance Amplifier that I need to implement in LTSpice. I need to choose a value for \$R_2\$ and \$C_{inf}\$ in order to have a (theoretical)gain value \$A_v=...
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Subthreshold Transconductance Amplifier

As part of a broader project, I am designing IC circuit using CMOS to one of the first steps I'm working on is the filtering a series of pulses with of the noise. The actual pulses are around 1 kHz so ...
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LTSpice Transconductance Amplifier Simulation

I'm trying to simulate a band-pass transconductance amplifier in LTSpice, which looks like this: I used the recommendations of this post - https://electronics.stackexchange.com/a/278870/87695 - and ...
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Op-Amp and MOSFET current source not behaving as expected

Based on the circuit from this page called transconductance amplifier, I decided to build an adjstable constant current source for up to 1.6A: Current is set by the voltage divider connected to the ...
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Calculate transfer function of transconductance amplifier circuit

How can I model/calculate the behavior from Vin to Iout of the following circuit? (Credits of the picture go to Analog Devices): Essentially, I am interested in the large signal response, such as a ...
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Transconductance amplifier question

I'm testing my first ever OP amp circuit and I ran into a problem. I have done the following circuit (see picture). The 0 - 3.3V called uC is coming from a Nordic nRF24LE1 PWM and RC filtered output. ...
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When should I be considering an operational transconductance amplifier (OTA)?

I found a few questions roughly related to this: How is a transconductance amplifier used to measure current? Operational Transconductance Amplifier Input Configurations Dead or alive: Operational ...
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How is a transconductance amplifier used to measure current?

In this post Design for a Precision LCR Meter the author says: Current is measured via a transconductance amplifier (again with programmable gain) which produces a voltage proportional to the ...
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Dead or alive: Operational transconductance amplifier

My first experience ever with an operational amplifier was with an LM3900 from a Philips experiments kit and these kits date from a long way back in time, when I was a young boy in primary school. I ...
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