Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

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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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 transconductance amplifier but not all have…
scanny
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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 rarely see designs with operational…
jippie
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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 I am implementing 2nd order sallen-key high pass…
J Dolan
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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 higher exceeding the bandwidth, the gain at which…
concerned middle age man
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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 equivalent model of the MOSFET. With this model I got…
Andrew Rusell
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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 ground. In my understanding, this should block…
Alex_G
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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). However, it states that the gain is: $$ g_m = {\Delta…
Jon Wingfield
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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 used a G component with a table to represent the…
w00t
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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 step at Vin. Using the standard scheme for single…
Junius
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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 current through it, but without the ‘burden voltage’…
Sam
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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 managed to put together a stable circuit from…
Alex_G
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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 voltage changes as well. From my point of view, I…
Madao
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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 op-amp input: Iout=Vdiv/Rlim On Multisim it works…
bleudoutremer
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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. I'm using a LM741CN op amp and try to follow the…
RedSmolf
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Can't compute the value of Resistance of Operational Transconductance Amplifier

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=1500\$. What I found is that: …
bicanul123
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