Electrical Engineering Stack Exchange
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Questions tagged [voltage-source]

Anything related to voltage sources, their circuit models and their practical circuit implementations. An ideal voltage source is a two terminal device whose output is a voltage signal with a given waveform regardless of its load, i.e. irrespective of the circuit to which is connected.

Anything related to voltage sources, their circuit models and their practical circuit implementations.

An ideal voltage source is a two terminal device whose output is a voltage signal with a given waveform regardless of its load, i.e. irrespective of the circuit to which is connected. Practical devices and circuits only approximate this behavior.

See Wikipedia on voltage source.

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Explain in layman's terms Vgs and Vgs(th) of MOSFET's

I'm trying to understand \$V_{GS}\$ of MOSFET transistor. From what I understand \$V_{GS}\$ normally stands for voltage gate to source breakdown, but other than that I lack an understanding. \$V_{GS(th)}\$ is the threshold voltage at which the…
Sam W
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What is the physical meaning of negative resistance?

I am a bit confused about the physical meaning of negative resistance. Mathematically, a component which has negative resistance shows a decreasing voltage across its terminal when the current inside it grows, and vice versa. But how is this…
Kinka-Byo
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LTspice: simulating the bounce effect of a push button

I'm trying to reproduce in LTspice the switching response of a push button with bounce effect as shown on the second page of the SN015 Support Note by Würth Elektronik. Here is an excerpt: What I have tried to do is use two voltage-controlled…
noeld
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How can I calculate the transfer function of a low-pass Sallen–Key filter?

I was looking at the following circuit. AFAIK, this is a low-pass Sallen–Key filter, with a VCVS instead of the op-amp. I started to work out the transfer function, but somehow I got lost at a certain step. First, you can use the common node to…
avelardo
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Ideal Voltage and Current Sources in series

For the circuit below determine a) the current I, b) the voltage \$ V_R \$ and c) the voltage \$ V_o \$ across the current source Note: VR should be V subscript R and the case is the same with Vo. The diagram above is from a set of lecture…
Carter Nichols
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Why do I get two different answers for the current through the 47 kΩ resistor when I do a source transformation?

If I replace the voltage source and 5 kΩ resistor on the left with the corresponding current source and resistor in parallel I get I = 192 µA (this is the correct answer as stated by the workbook). However, when I replace the right side current…
zoghii
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LTspice: Noise of frequency-dependent resistor in noise simulation

When placing a frequency-dependent resistor in LTspice using the Laplace statement the result of an ac simulation (right circuit) looks fine: However, when I use the same frequency-dependent resistor in a noise simulation (left circuit) the result…
Charly
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Why is the voltage divider formula used in this circuit to find the terminal voltage?

I'm going through the book Practical Electronics for Inventors and there is a chapter about voltage sources that talks about practical voltage sources. It calculates the terminal voltage of the circuit below using the voltage divider formula. Why…
Vio Ariton
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Do batteries (voltage sources) supply constant voltage?

I know that voltage sources are those that can supply constant voltage. The producing current may vary with the load. Suppose I have a rechargeable battery. I fully charged it and started using it. After some time I have to charge it again. I'm not…
Raihan Khalil
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How does one know that the current is flowing downwards through the \$8 \ \Omega\$ resistor?

I'm currently studying the textbook Fundamentals of Electric Circuits, 7th edition, by Charles Alexander and Matthew Sadiku. Chapter 1.7 Problem Solving gives the following example: Example 1.10 Solve for the current flowing through the \$8 \…
The Pointer
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Finding load current in a circuit with voltage dependent voltage source

This question has been rolled back to the version that doesn't invalidate the answers (edit by Andy aka) I'm currently studying for my Circuit Analysis class, the teacher shared some questions and their answers with us, but not the steps of…
Berkay Günaydın
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MOSFET turn on/off curves misunderstanding

The MOSFET's turn on/off curves have a part where the drain current and the voltage across Drain-Source are not zero. That's where most of the switching dissipation happens. The problem I have is in T1-T2 section (see figure below). If the source…
HatimB
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Don't individual signal sources affect each other when using a summing amplifier?

I am studying the book Electric Circuits by Nilsson & Riedel. There I learned about "summing amplifiers" and how to derive equations by applying KCL at inverting input of the op amp. I see that solving equations result in this "voltage adding"…
alpersunter
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Create circuit from current–voltage characteristic

I'm trying to create a circuit from a given current–voltage characteristic like this: I want to use ideal diodes/ideal voltage source/ideal current source So my idea was for the dotted graph the left circuit and for the solid graph the right…
Sam
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LTspice dependent voltage sources circuit

I am trying to add dependent voltage sources in LTSpice, but I need to make a voltage dependent source whose voltage depends on the average of two voltages. How can I build that in LTspice? The circuit is like in image,
ifrah
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