# Questions tagged [circuit-analysis]

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

5,746 questions
Filter by
Sorted by
Tagged with
29 views

### Formula for Charging Capacitor in special diagram: Series + Parallel

Given the following circuit: First things first: Is the resistor, that is dashed and transparent, really necessary if the switch is in position 1? If so, what are the formula for charging the ...
• 101
35 views

### Sensitivity of Inrush Current Circuit

I'm new to LTSpice and analog design - I'm having a bit of a struggle getting a feel for the behavior of this inrush limiting circuit. Stole the design from another SE post, but playing with the ...
• 21
127 views

### Is this cascoded opamp structure unstable by design (LTspice)?

I am playing with a cascode op-amp design and I have problems judging its stability (schematic at the end of the post). When I judge the DC or AC analyses, it all looks good. No peaking and good phase ...
• 12.1k
53 views

### Turn off high side switch

I am trying to turn off my N-channel MOSFET which is driven by a charge pump. It takes too long to discharge the pump through the gate-resistor to ground, therefore the power dissipation is very high....
• 13
109 views

### Is it realistic to analyze the bare components / ICs of circuit boards to understand how they work? [closed]

I am trying to learn as much as I possibly can about electronics by doing my own personal projects. I am wondering if you guys think it would be worth my time to analyze bare circuit boards and their ...
• 536
1 vote
65 views

### Analysis of circuit with dependent voltage source with no apparent solution

This is an exercise from Irwin's book, 9th edition. simulate this circuit – Schematic created using CircuitLab Although the book calls for the use of nodal analysis, I decided to do it by mesh ...
• 185
93 views

### Need help to understand op-amp input resistor and capacitor network

I'm trying to understand the circuit design from this application note. Here is the figure: The author said: Resistor RIN provides a dc return path for the VS/2 reference voltage and sets the ...
45 views

### Situation with controlled source in Mesh Analysis. Situations without solution?

I was analyzing the circuit below, and by using Mesh Analysis (this I am currently practicing), I obtained that the voltage at the $6k\Omega$ resistor (R6) is $9V$. I was able to work this out and ...
• 185
44 views

### RHP pole of two stage OTA

I learnt that for any amplifier (with some capacitor) if we short/open the capacitor and the polarity of gain changes, it is a sign of RHP zero. Now, while applying the same analysis I obsevred that ...
• 199
67 views

### How to become a expert in electronics circuit design in embedded product development? [closed]

I want to design electronics circuit for embedded product development. Currently I have a project where we have to design the ECU and BCM of automotive vehicle.
1 vote
69 views

### Trying to implement an exponential averaging circuit

With basis in this: If i wanted an exponential averaging circuit with time constant t = 35ms i would just use this equation : t = RC where i can choose one value for R and compute C. What i dont ...
• 493
59 views

### $m \times n$ grid of resistors, power dissipated through each is $P_{total}/ (m \times n)$

$m \times n$ grid of resistors (all of which are the same), power dissipated through each is $P_{total}/ (m \times n)$ ? I just want to confirm my thinking: If the power is $P = IV$ the ...
1 vote
195 views

### What voltage to expect on the resistor in RC circuit?

Please help me understand how the voltage signal changes on the resistor in the attached RC circuit. My expectation would be that when the source of the AC voltage signal (PR2) is in the positive part ...
• 11
65 views

### Motor Controller Cloning Service? [closed]

I am a total amateur and seek the hardware engineer wizards that frequent this website, lol. Anyway, does there exist a service to clone a PCB given just a few pictures? Does a service exist that will ...
• 1
36 views

### Determine the absorbed complex power (AC Circuit Power Analysis)

I've been trying to solve a book problem from Hayt, et al. Engineering Circuit Analysis (8th Ed.) —Practice Problem 11.9. And here's my latest attempt, I just can't see what I'm doing wrong, why I ...
281 views

### Strange waveform observed using push-pull configuration when connecting an inductor

I connected an inductor to the output of a simple class-B transistor amplifier, which was discussed in a Renesis application note. Then I applied a pure sinewave signal to the input and I observed a ...
• 33
1 vote
133 views

### Load line analysis

You are to design a network of resistors to be used in the circuit, such that iD = 1 mA when the diode is connected, and vS = 2 V when the diode is disconnected. Normally questions like this would ...
• 65
93 views

### Is the fact that voltage drop is equivalent for each branch of a parallel circuit derived from Ohm's law or physical observation? [closed]

e.g. In the above image voltage drop is equivalent across each parallel branch even though each branch has different resistance values. Was this fact derived from manipulation of Ohm's law or through ...
74 views

### Voltage drop resistor circuit unexpected voltage

I am playing around with voltage drop resistor circuit, but the output voltage doesn't match the voltage I calculated. This is the formula I am using Vout = Vs*R2/(R1+R2) simulate this circuit –...
35 views

### CAN Bus acknowledge error

I'm seeing signals from my CAN bus that look like good messages, but then I receive an "incomplete packet" error after the full/almost full message has been sent. I've viewed this on my ...
1 vote
117 views

### Antenna pi-network matching High or low pass?

I am a beginner in RF system design and I have some questions. I have a PCB trace antenna, I need to tune it to 2.45GHz, this is for Bluetooth low energy communication. I want to use a pi-network for ...
43 views

• 525
65 views

### In master side HART protocol hardware: how HART voltage applied across sense resistance, can be received in slave side?

I’m trying to test a HART hardware both in master side and slave side , I’m using A5191HRT HART modem IC from Onsemi, (because only its HART modem IC founded in shops our city), the biggest ...
84 views

### Voltage across the inductor

If the value of R is 5 ohm in the circuit and the switch is closed for a long time and then the switch is opened at t = 0 then what will be the voltage across the inductor? Will it be equal to the ...
• 880
68 views

### Current direction inconsistency in Nodal Analysis

I'm very confused here! Most of the times I'm getting wrong answers or impossible equations because of this - even if I know the procedures for the analysis. It has to do with setting up nodal ...
• 525
1 vote
75 views

### What is this strange harmonic content present in a resonant circuit output waveform?

The following is an LC circuit excited at resonant frequency 15.915Hz (L=10mH, C=10mF.) I would expect the output to have only the resonant frequency (constantly increasing in amplitude) since the AC ...
• 2,165
46 views

### Equivalent resistance in simple Current Circuit

I have the following circuit (below). In order to calculate the current I1 as a function of the resistors and the voltage of the circuit, I'm doing the following: ...
• 525
120 views

### Find capacitance such that voltage and current are in phase

I just cannot solve this exercice, any help? This is what I have tried:
1 vote
66 views

### What is wrong with this MOSFET differential pair analysis?

I am confused regarding the analysis of the circuit on the left and its small-signal equivalent circuit on the right: simulate this circuit – Schematic created using CircuitLab Here is my ...
• 315
1 vote
106 views

### DC-DC Converter MCP16331 doesn't work (at all?)

I am trying to implement the DC-DC buck converter MCP16331 to my design. The circuit is powered by a 24 VDC power supply (DAUER+). The MCP16331s job is to regulate the 5 V needed to power µC, ADC, ...
• 19
68 views

### First-order RC circuit

I have a first-order RC circuit without source and capacitors initially charged to +5 V and -4 V as shown in the figure. Initially charge sharing takes place between capacitors and v(a) = v(b) = 0.5 V....
71 views

### LM22673 diode selection

I'm fairly new to electronics, and in my project I'm using LM22673 as Buck Converter in this Diode selection parts this is given which is confusing for me. as Ultra-fast diodes can switch very fast, ...
• 35
469 views

### Order of an RC circuit

The circuit contains two independent state variables but the output of the circuit simulated in LT spice shows a first-order response. Where am I wrong?
76 views

### Self biased transistor current limiter

I am analysing the below self biased transistor circuit and have some questions: Why does the transistor in self biased arrangement never go into saturation for a light load? When the emitter ...
• 165
127 views

### Why does this inverter circuit behave like an amplifier?

connect a large value DC bias resistor, to form a CMOS amplifier as shown in the diagram (74HC04 and the 74HCU04 chips)
• 19
77 views

### Why are these resistors used? What is their function in this BQ76920 circuit?

I am designing a BMS using a TI BQ76920 connected to an ATmega328P via I2C. I'm using the design in the datasheet as my reference. I am confused about why and how these resistors are being used in the ...
• 35
34 views

### APD (Avalanche Photodiode) Active Quenching Circuit (AQC) Waveforms & Circuit Behavior

I am reading a paper tiled Avalanche photodiodes and quenching circuits for single-photon detection The paper presents an Active Quenching Circuit schematic, briefly describes its operation, and shows ...
47 views

### Faulty PNP Transistor switch fix...what is causing the noise on the base?

I built a ham radio amplifier kit that takes about 5 watts drive and makes 70 watts. It is called a MiniPA70. Here is a website someone put together describing its build/use. http://pa-11019.blogspot....
1 vote
90 views

### Confused by voltage and voltage drop with different kinds of power supplies

I found a voltage drop behaviour that I don't understand and would like some help please. I have a simple circuit connected to my Arduino: I have two circuits like this, where the only difference is ...
64 views

### How can we know that when n1 and n2 is 1, the output is 0? What makes the circuit a NAND?

We start with the obvious part of the circuit, N1 and N2 are in series. I was given the truth table, where both N1 and N2 are 1, then the output is 0 and the rest is 1. By this picture, how can we ...
• 13
131 views

### Why does voltage decrease as resistor increases?

As you can see in the images below, when I increase the resistor value from 200 Ω to 2 kΩ, the voltage at the node Vd suddenly decreases. Why is this so?
55 views

### Questions on Vss for op-amps (differential amplifier)

I was working on a voltage amplifier and confronted the following problem regarding Vss of the op-amps. The op-amps I am using are MCP603T-I/Ps. The circuit diagram is as shown below. (INSTRUMENTATION ...
1 vote
23 views

### PN circuit, playing with doped wafers

So I have two silicon wafers. One is P type (doped with boron) and one is N type (doped with phosphorus). I am just playing around with these and thought to myself, "can I make a diode if I ...
106 views

### Good way to obtain voltages along (non-uniform) $RC$ line

I have a long RC line, e.g.: simulate this circuit – Schematic created using CircuitLab Is there a good way to obtain the voltages on nodes V1, ..., Vn (possibly approximated) at a specific ...
• 1,238
538 views

### Zener Diode Transient Behaviour

I'm learning how Zener diodes can regulate voltage. Can you help me check if my understanding of its transient behaviour is correct? Say that the Zener diode in the diagram is in its conducting state, ...
• 181
81 views

### How can I analyze following circuit? [closed]

I have an electronic homework. I wonder how I can analyze and specify values of resistors and capacitors? 3 V < Vout < 30 V Max Iout = 3 A Finally, what is the name of this circuit?
I'm reading AoE, there is a figure (p.26) for RC differentiator output and input voltages for step 5V input voltage with different slew rates ($dV_{in}/dt$). (It's time domain part. Only the rising ...