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Answer by periblepsis for How to find the RMS value of a triangular function...
The whole idea behind RMS voltage or current has to do with the equivalent DC level that would yield the same power into a load. So it's about the topic of...
View ArticleAnswer by periblepsis for 74181 A=B behaves differently in Logisim Evolution
Yes, the way the 74181 is arranged all four outputs, \$F_3\dots F_0\$, must be 1 in order for the A=B output to be 1. That's clear from the schematic and there's no questioning that fact.If you want it...
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Answer by periblepsis for How can I fix a conceptual misunderstanding about...
I'll stick with the injection version of the DC (level 1) Ebers-Moll model. It was the first description made and it is more intuitive. So I imagine it may provide a better shot at it. (I will...
View ArticleComment by periblepsis on What could be causing a difference between LTspice...
@SteKulov LTspice does flag an error -- one that specifically mentions the floating node and the current source.
View ArticleAnswer by periblepsis for Thevenin`s Theorem (Thevenin`s resistance)
I can't say if it will help you, since each of us have sometimes very different ways of thinking about the world we've found helpful, but perhaps try this idea. Imagine applying a \$1\:\text{A}\$...
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Answer by periblepsis for Thevenin theorem conditions and inquiries?
First off, they are trying to get you to use superposition methods. (I'd avoid that step and go directly to the solution.) Second, they write elsewhere, as you quote, "Alternatively, the dependent...
View ArticleComment by periblepsis on Thevenin and Norton shortcuts
@dareen I've added another option. I can think of a few more without any effort. Hopefully, someone else will provide those.
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Answer by periblepsis for Is this question impossible to solve using the...
You know the following is true, given that you were able to already calculate that \$i_3=15\:\text{mA}\$:Here's an LTspice schematic that replicates yours:Note that I can set \$v_3\$ to anything from...
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Answer by periblepsis for Am I correctly solving this circuit with Ebers-Moll?
You can ignore the reverse-biased BC junction diode. So the injection version schematic boils down to:simulate this circuit– Schematic created using CircuitLabInjection version model, less the...
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Answer by periblepsis for Weird simulation results with BJT NPN transistor
qualitative explanationI just recently wrote about how to use a version of the Ebers-Moll model to make predictions for cases like this. Your circuit was put into saturation when you added the...
View ArticleComment by periblepsis on Why two types of critically damped response...
@Kuba It's the seventh edition. How can they keep seeing this text that keeps screaming out for improvement as it obviously does so loudly? And I'm sure a few grad students involved in editing must...
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Answer by periblepsis for Determining Thevenin Equivalent of a Circuit with...
The method to apply a \$1\:\text{A}\$ source, to work out the thevenin resistance, is something like this:Using KCL with SymPy (free) as a solver:values = { r1:1, r2:1, i1:4 }eqx = Eq( vx/r1 + vx/r2,...
View ArticleComment by periblepsis on Fundamentals of Electronic circuits book Example 7.15
@Daniel :) Yes. Written many hours later. But perhaps better for you?
View ArticleComment by periblepsis on Class AB Amplifier with feedback
@greybeard Good enough. Let's go with that. Since I didn't give it a moment's thought. Thanks.
View ArticleAnswer by periblepsis for Using Kirchhoff's current law, how is this first...
You only have three unknown node values. Using SymPy (free) you may write:eqA = Eq( va/R1 + va/R2 + va/R7, v/R1 + vb/R7 )eqB = Eq( vb/R3 + vb/R4 + vb/R7 + vb/R8, va/R7 + vc/R8 + v/R3 )eqC = Eq( vc/R5 +...
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Answer by periblepsis for 7-segment numeric counter that only displays...
A push-button is a notorious source of glitches as it settles one way or another. So it will need debouncing. Ben Eater's 8-bit computer uses a 555 for this purpose (also available in CMOS...
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Answer by periblepsis for Transistor circuit
What you have is essentially this:simulate this circuit– Schematic created using CircuitLabIf we assume about \$700\:\text{mV}\$ for the \$V_{_\text{BE}}\$ junction of the NPN, tentatively, and...
View ArticleAnswer by periblepsis for Solving an RLC network problem with Kirchoff's laws?
I'll avoid attempting direct answers to the questions. I'm not entirely sure about what #2 is asking, anyway. So it's better I avoid any interpretation and instead focus on what you wrote:I'd like a...
View ArticleComment by periblepsis on Calculating voltage drop
@TIMDRIPCAN If you mean over on the left side then it's just a simple resistor divider that can be converted from three parts (ideal voltage source, plus two resistors) to just two parts -- a new ideal...
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Answer by periblepsis for Current limiting circuit behaves not as expected
That's not a very good circuit.From a very simplistic view, you can consider the bipolar's \$V_{_\text{BE}}\approx 700\:\text{mV}\$, that bypasses both diodes. This means that from a first order...
View ArticleComment by periblepsis on What happens to the capacitor and inductor if net...
@M.SaaminRahman If I'm reading you well, then yes. That's a good way to put it. The idea of reactive power is for the equilibrium state, which is arrived at after some time passes. The fuller equations...
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Answer by periblepsis for Use of Inductors in Low Pass Filter
I am wondering if there can be other variations to achieve this secondorder low pass filter.Sallen & Key discussed a large catalog of 2nd order active networks in their 1955 paper. Not just the one...
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Answer by periblepsis for KVL Method - Currents Signs on the equation
There are rules, such as the passive sign convention, and there are other rules (which shall remain unnamed as I don't like them.)So long as you use logically consistent rules and apply them...
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Answer by periblepsis for Understanding Gas Sensor Output Voltage from...
your questionIt's almost impossible to guess at your professor's motivations for remaining somewhat opaque in conversations with you. If I had to throw mud at the wall as a guess, I'd say that you are...
View ArticleAnswer by periblepsis for How many volts is the potential \$V_x\$ when only...
I get:$$\begin{align*}0\:\text{V}+V_1 - R_1\cdot I_1 - R_4\cdot\left(I_1-I_2\right)&=0\:\text{V}\tag{mesh 1}\\\\0\:\text{V}- R_4\cdot\left(I_2-I_1\right)-R_2\cdot...
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Answer by periblepsis for Designing a Sallen-Key Band Pass Filter
Let me expand your diagram:simulate this circuit– Schematic created using CircuitLabI don't know if this is what your notes used. But it's what came to mind when reading the equations you provided. If...
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Answer by periblepsis for Mesh analysis method
Your question could have been better with a little extra time added to improve its readability. But I may have the gist of it.I'll call your loop currents \$J_1\dots J_4\$ and accept your use of \$I\$...
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Answer by periblepsis for How to identify the terminology of Common Amplifiers?
I went through a similar process of trying to understand books teaching these same three configurations.(Also, at that time, I didn't know about single-ended vs differential modes for signalling. The...
View ArticleComment by periblepsis on DIY Contact Mic Amplifier – Struggling with Noise &...
What exactly is the microphone part number/type.
View ArticleComment by periblepsis on Common-Emitter Darlington Circuit – Theoretical...
Manuel, Also please include a snapshot of the output signal showing 5 or 6 cycles across R3 and across R2, too. And are those ideal NPN transistors?
View ArticleComment by periblepsis on Op-amp with current amplifier
@efaa The bipolars, if not included in the feedback loop, actually reduce the voltage gain. Not by much. Perhaps to 98% or 99%. But it's not 100%. Also, Null's link and image shows a much better...
View ArticleComment by periblepsis on Problem with measuring the saturation voltage of a...
@wewqewqewq High level injection effects and ohmic resistance get conflated into measurements made at 800 mA. Not knowing the exact details of your procedure, I also worry about heating effects making...
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Answer by periblepsis for Common-Emitter Darlington Circuit – Theoretical...
you can't get there from hereWith your amplifier topology, the open loop voltage gain is approximately the quiescent voltage across the collector resistor divided by the quiescent voltage across the...
View ArticleAnswer by periblepsis for Forward voltage of the 1N4001 diode is not 0.7 V
Any forward bias with a diode, even a very small applied voltage, will lead to some diode current.Taking a look at your data table, it appears to me that your measurements with smaller applied voltages...
View ArticleComment by periblepsis on Limited gain on BJT differential Op Amp
First time I've seen this done. Learned something new. ;)
View ArticleComment by periblepsis on Calculate Base Voltage in two-transistor current...
@jonathanjo Have you already read this answer. It covers almost everything you are asking for. Perhaps more than that.
View ArticleComment by periblepsis on Precision Signal Amplifier Circuit - 2Vpp to 200Vpp
You aren't going to get class-AB 20 Vpp from a 20 V supply rail. Some voltage margin is required. Especially at 20 watts! Also, define "minimal latency, low distortion, and high fidelity." And do you...
View ArticleComment by periblepsis on Charging time of a capacitor for a differential RC...
For sample and hold, you need several \$\tau\$'s. Not just one. How many will depend on the application requirements.
View ArticleComment by periblepsis on Find maximum and minimum between 2 and 3 Numbers
@erifaerifa By 2's complement do you mean signed? There's some ambiguity in usage, from experience. So I'd like to be sure about it.
View ArticleComment by periblepsis on Circuit analysis with impedances
I believe I'm seeing a re-opened question. You have computed \$Z_1\$ and \$Z_2\$, correctly. Also, the series equivalent total impedance, as well, is correct. And although I might express the current...
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