# Questions tagged [circuit-analysis]

Circuit (Network) analysis is the process of finding the voltages across, and the currents through, every component in the network.

2,987 questions
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### Op-amp problem, two inverting amplifiers?

So I stumbled across a rather strange ideal op-amp circuit that I've never encountered before. I've done enough problems regarding inverting amplifiers, non-inverting, summing, difference, and such, ...
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### How to find voltage across resistors in RC Circuit with 2 voltage sources?

I've been struggling with this difficult RC circuit that asks for the voltage, Vo, across the R4 resistor. Edit: Assume that the switch has been opened for a long time, before it is closed at time t ...
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### How to decide on the values of a set of resistors for a circuit?

Say i have a PN2222 transistor that i want to integrate into a circuit to amplify a signal with a gain of 100 or so. From the datasheet of the transistor i can determine that ...
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### Finding total energy for RC discharged capacitor at t = ∞?

Most Rc circuits are not as severely difficult as this kind of circuit. I'm trying to solve for both the time constant and the voltage V2 across the R2 resistor, both of which will hold the necessary ...
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### RL Circuit Analysis with 2 sources, how to find current of resistor?

I've been tackling some problems related to natural and step responses for RL & RC circuits, but I think I've hit a major roadblock for this RL circuit. I'm trying to find the time constant and ...
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### Can a dependent voltage/current source have some impedence/admittance,respectively?

Im studying 2-port networks, for Z parameters equations, there is general equivalent circuit given, in which dependent voltage source is given, I do know about dependent voltage sources, but do these ...
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### Derivation of $Z_{och}$ & $Z_{sch}$ for a symmetrical lattice two port network

I've been trying to proof the open circuit impedance of half circuit [i.e $Z_{och}$ ] and short circuit impedance of half circuit [i.e $Z_{sch}$ ] of symmetric lattice two port network (which is ...
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### Input offset voltage for microphone circuit

Does anyone know what's the input offset voltage (oscillated 2.5V) to the op-amp in the circuit for? From my understanding, the input offset voltage needs to be extremely small so that output DC ...
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### How to calculate the transfer function?

I have The following circuit network (link to multisim) and i am asked to find the transfer function, the max and min value, the cutoff frequency, angle and the type of the filter. [the actual ...
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### MOC3021 optocoupler not working ( or not working , a bit confused )

My Understanding As far as my understanding of MOC3021 optocoupler goes, it should latch pins 4 and 6 whenever there's a current flow between pins 1 and 3. The Confusion Image 1 - D1 not glowing ...
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### 741 Op. Amp.: Inverting input connected to output (pin 2 connected to pin 6). What does it mean?

simulate this circuit – Schematic created using CircuitLab I am a newbie electronics students. My question is, what does it mean (what happens) when you connect pin 2 to pin 6 on a 741 op. ...
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### Best way to monitor on/off state with a microcontroller

I have 3D printer with a cooling fan that by design is on constantly, however it only needs to be on when there is something to cool! I have no idea why they have it on all the time since it is loud ...
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### Rising edge duration of a low to high pulse

In a device I am using, I see the following in the description... "At start-up, the module requires an ON_OFF pulse sent from the host. A second pulse sent from the host will re-enter hibernate mode. ...
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### Q: How to remove DC offset

simulate this circuit – Schematic created using CircuitLab Essentially my goal is to measure Node A and feed Node C into the arduino for further measuring. What I attempted was use a buffer ...
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### Derivation of time constant for single source, single capacitor RC circuit

Take a circuit comprised of resistors, a single capacitor, and a single step response voltage source. Then: Every single voltage and current in the circuit, except at the voltage source, will have a *...
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### ESD strike breaks the LAN8742A ethernet phy

My circuit uses LAN8742A ethernet phy. The system has a metal case and gets 220V AC to power supply board. After converting 5V DC it goes to my board that has Ethernet and mcu. I screwed case and ...
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### Zero crossing detection circuit correct?

I am working on a DIY AC dimmer circuit with arduino. This project is part of the AC dimmer circuit as mentioned here Since, I was stuck in so thought of retracing my steps and checking each part of ...
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### Parallel MOSFET Circuit Analysis

I'm solving part b of this question I started with the assumption that both MOSFETs were in saturation mode to simplify calculations, I then solved for the circuit, tested the assumption using vds, ...
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### What are the limiting factors of these op-amps?

I designed a multiple feedback band pass filter ...
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### Does anyone know how the Boss Metalzone sweepable mids affect the bandpass?

https://electricdruid.net/boss-mt-2-metal-zone-pedal-analysis/ http://sound.whsites.net/project150.htm Like in the original question - I'm struggling to understand the relationship between the op-amp ...
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### Does anyone know how the low tone control of the Boss Metalzone works?

https://electricdruid.net/boss-mt-2-metal-zone-pedal-analysis/ http://sound.whsites.net/articles/gyrator-filters.htm#s9 I have been using these websites to try and work out how the eq works, but I'...
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### Conceptual paradox with resistance in loop/node analysis

There are loop/mesh analysis and node analysis corresponding to Kirchhoff’s voltage law (KVL) and Kirchhoff’s current law (KCL), respectively. Let's consider three elements, R,L,C, connected ...