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How to simplify this AC electrical circuit

You've put some work into thinking through some of the KCL and I can see better where you need help. Here's the KCL: $$\begin{align*} \frac{U_1}{5\:\Omega}+\frac{U_1}{j\,4}&=\frac{U_2}{j\,4}+2\:\...
periblepsis's user avatar
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What is the basic idea behind the so-called "improved Howland current source"?

Basic idea The "improved" solution is not Howland's doing. Rather, it is named later after him as a sign of appreciation and respect. However, it is interesting that the two circuit ...
Circuit fantasist's user avatar
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Using a N-channel JFET as a current source

@qrk, I agree with you that we better trust the datasheet but the formula gives me an idea what MOSFETs to investigate. Instead of looking up all 1000+ that are in the LTspice file "standard.jft&...
hennep's user avatar
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1 vote

Howland circuit gain factor

The voltage across R5 is VR5 = -Vвх.R3/R1. So, the load current Iвых flowing through R5 and accordingly, through Rн, is Iвых = VR5/R5 = - Vвх.R3/R1/R5. If R1 = R2 = R3 = R4, Iвых = -Vвх/R5. Brilliant ...
Circuit fantasist's user avatar
1 vote
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Howland circuit gain factor

This circuit seems to be an "improved" Howland circuit. Here is how it should be "solved" ... Maple sheet. The current I solved is the current in R2 resistor. Note how R5 and RH ...
Antonio51's user avatar
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2 votes
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Using a N-channel JFET as a current source

A thread on the maker.pro forums suggests $$ I_{drain} = {BETA \; (1 + LAMBDA \; V_{ds})\;(V_{gs} - VTO)^2 } $$ I would rather trust the data sheet than a SPICE model for figuring out \$I_{DSS}\$.
qrk's user avatar
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Paralleling Multibit current DAC: Improving Accuracy by Averaging

On average, yes across thousands of completed circuits, that would be true - the average linearity will go up. However, the per device variance will go up proportional to the number of devices. Think ...
MOSFET's user avatar
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3 votes
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Current DAC/current wave-form generator

Your MCU (STM32L476) is able to do that by its onboard DAC and external opamp. Your DAC is able to run up to 10Msps https://www.st.com/resource/en/application_note/an4566-extending-the-dac-performance-...
Michal Dudka's user avatar

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