Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [transconductance]

The transconductance of a device relates the current through the output of the device to the voltage across the input of the device.

The transconductance of a device relates the current through the output of the device to the voltage across the input of the device. The SI unit of transconductance is the Siemens, which uses the symbol S.

See Wikipedia's article on transconductance for more information.

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Can a floating capacitor terminal be used to collect electrons?

I want to collect charge from an electron beam source. For that, I'm proposing to put a floating capacitor with its bottom terminal floating and directly exposed to the electron beam gun. The top terminal would be connected to a transconductance…
Jorge Johanny Sáenz Noval
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Understanding Operational Transconductance Amplifiers

I understand the high-level function of OTAs, that they provide an output current proportional to an input voltage. But what I don't understand, and what I can't seem to find any information on online, is exactly how they're used and what the…
Hearth
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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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Why is higher transconductance relates to faster transistor switch?

Here is a quote from this site: ...higher 'transconductance' - a measure of the performance of a transistor - than silicon transistors. The higher the transconductance, the faster the transistor can switch on and off. That means higher clock…
user16307
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Is the OPA860 a diamond transistor?

I was looking at using the OPA860 for a voltage controlled load. Reading in the OPA860 datasheet it says: The OPA860 combines a high-performance buffer with a transconductance section. This transconductance section is discussed in the OTA The …
Voltage Spike
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Interview Question

This Circuit was given. I know every component of this circuit individually, I know feedback and gain margin and transconductance amplifier. But the problem is how to start? first, I was thinking to find the Transfer function but the problem is no…
Nitish
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Interpreting the value of transconductance shown in a MOSFET datasheet. Why was that particular value chosen to be shown?

Context: I'm a beginner in electronics, self studying MOSFETS. I'm trying to understand why the manufacturer of this MOSFET decided to provide a single particular transconductance value in the datasheet. I would like to understand why the…
Joaquin Brandan
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Constant-gm bias circuit

I am doing a study on Improvements in biasing and compensation of CMOS opamp. Do you guys know how to come up with the equation for RDS4C ?
kevin998x
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Bidirectional voltage-to-current converter

How to make the following voltage-to-current converter bidirectional, so that bidirectional current can be driven through the load?
George Robinson
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LM13700 Gain Calculation

I pulled some LM13700 OTAs from an old board and tested them. All voltages, currents, and resistances were measured. I had the expected (approximate) voltage gain using the equation \$ A=(R_2/(R_1+R_2 ))*g_m*R_L \$ where gm equals \$ 19.2*Iabc…
apoch
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Transconductance value in LTSpice

I am trying to work out how to specify the transconductance value or Kn for LTspice. I have a part I can't find a suitable model for so I'll need to create one. I've tried this before and got values that ended up being entirely wrong. So I'm trying…
richbai90
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How does the Early effect limit the voltage gain?

As far as I understand, the Early effect increases the quiescent \$I_C\$ for a given \$V_{CE}\$. At the same time texts treat this effect as a limiting factor for the gain. Here is an excerpt from a text: There is one additional quantity we will…
pnatk
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Error Amplifier Gain

I was studying the "SG3525" IC and its functions, and I encountered this issue: In the "Error Amplifier" section of the Datasheet, there is a parameter that named "DC trans-conductance" which it is "1.5mS" typically. At the bottom of the page it is…
Mohammad Hussain Asadzadeh
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Measuring transconductance of any circuit

May I know if the following transconductance measurement test circuit is correct because I am getting quite small Gm values ? I suspect that I need to use some derivative function because changing the mosfets width by a large factor does not change…
kevin998x
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Is transconductance concept more important for FETs than in BJTs

In some texts I encounter they mention transconductance when it comes to FETs not BJTs. I have seen myself many texts and skimmed through them, the word transconductance does not appear until FETs. Before they teach BJTs and they use hfe and other…
user1245
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