A fundamental electronic component that stores energy in an electric field, commonly used in filtering applications.

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3answers
91 views

Inverse Laplace Transform of RLC Circuit

The voltage across the power source equals the summed voltage across the resistor, capacitor, and inductor at any time (t). This is shown in the equation below: ...
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1answer
63 views

Spanning high voltage between capacitors in series

first of all thanks for your time. I've studied a lot before to make this post but theory and real world rarely make a good marriage. I have 20kVAC of spike coming from an ignition coil (the one ...
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2answers
99 views

Capacitor between emitter and collector

What is the purpose of capacitor C5 ? I know it provides positive feedback to sustain the LC oscillations, but how does this work ?
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1answer
63 views

Code on capacitors

I accidentally let the magic smoke out of two (tantalum?) capacitors, one on an Arduino-based board and one on an RF reciever. Apparently they don't like being hooked up backwards. :-) For the ...
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1answer
32 views

Calculating capacitance required for a pulse duration of time T using a class AB amplifier

Firstly I apologise if this question is similar to another one I asked a while ago. But, as you will see, this is question is slightly different. I have an amplifier which is a common emitter driving ...
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1answer
51 views

Leakage from MOSFET Switch To Ground

I built this circuit at home to for science (I explicitly drew the body diodes for clarity). simulate this circuit – Schematic created using CircuitLab Imagine the following scenario: ...
4
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2answers
569 views

What are these capacitors?

I came across these capacitors in a kit and was wondering what type they are so I can buy more for use in button debouncing circuits. Unless I'm reading them wrong, they are 220 nF and 100 nF ...
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1answer
94 views

Capacitor placement / count

I'm building a circuit that has a number of servos on it. To eliminate servo chatter, I've seen recommendations to put in a 250uF cap (for the size servos I'm using). That much I can follow. The ...
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1answer
93 views

Schematic notation for decoupling capacitor?

I'm wondering where this capacitor should be placed. Is it a decoupling capacitor? There are two supply rails on this particular op-amp, so I'm assuming that this indicates I need to put one between ...
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0answers
45 views

Wheatstone bridge with capacitors [closed]

see picture. Not really sure how to prove this
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3answers
71 views

AVcc, and capacitor, using ADC

I am using Atmega328P to read temperature from LM35 and display it on the LCD (along with few several things it does). I want to understand the capacitor and connections for the AVR itself and AVcc. ...
2
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2answers
560 views

Will a large capacitor damage a circuit

I have 32 servos running from a 7.5V battery rated at 2500mAh and I'm sure that it has enough power to handle the servos, but it doesn't look like it can handle all of the servos pushing at once. I ...
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1answer
49 views

Axial inductor between the plates of a cylindrical capacitor

What happens if you put an axial inductor between the plates of a cylindrical capacitor (capacitor supplied with AC signal)?
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3answers
1k views

Why too many capacitors in parallel for Vdd supply net? Can't we just add all to replace with one big capacitor?

I have given the image of Basys-2 board's power regulator IC and filters connected to it in schematic. This is just an example but this is pretty much a similar filtering design for most of the supply ...
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3answers
77 views

Current flow due to capacitor in a basic power supply circuit

In a basic power supply like this one below, for a positive half-cycle the capacitor is charged up along with the rectified load current. For negative half-cycle diode is "off", so no conduction from ...
0
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2answers
79 views

Can I choose different value capacitor? [closed]

Our sewing machine's foot controller is running continuously and I need to change the capacitor but I cannot find the same value capacitor i.e 0.05 μF and 250 volt AC. I just want to know that can ...
0
votes
1answer
37 views

Impulse Response of a series RC filter where the output voltage is taken across the Capacitor

I am finding it difficult to understand the steps to derive the impulse response of a series RC filter where the output voltage is taken across the capacitor, the equation to derive is: h(t)= (1/RC) ...
2
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1answer
104 views

Why is there a 100nF capacitor in the Arduino Severino reset line?

While looking at the Arduino Severino (Single-Sided Serial Board V3) schematics I notice it has a ceramic 100nF capacitor in the reset line (marked in red in the picture below). My questions are: ...
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1answer
67 views

FM transmitter feedback capacitor [closed]

Why is a capacitor connected across the collector-emitter of the transistor? How does this capacitor prevent decay of LC oscillations?
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0answers
95 views

Capacitance of two wires with a grounded wire between

I have measured the capacitance between wires number, say, 1 and 3. With the wiree #2 just floating, the result was 390 pF. But after i have grounded the wiree #2, the capacitance was 220 pF. What is ...
1
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0answers
63 views

Voltage reading on Capacitors [closed]

I'm new to this and trying to fix a monitor with potentially bad capacitors. I noticed that a couple of my 16v 100uF capacitors have a 0.036 reading on my voltmeter, yet all others of the same and ...
11
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5answers
581 views

choosing type of capacitor

So I'm building a small audio mixer (or rather planning to do so) and I'm about to go shopping components and it's a jungle out there. My circuit says plainly 1uF with the regular capacitor symbol. ...
0
votes
2answers
84 views

what will be the resistor to find the time constant?

simulate this circuit – Schematic created using CircuitLab What resistance should I use to find the time constant? is it 30 ohm or 1130 ohm? what if the capacitor is an inductor will I be ...
0
votes
1answer
64 views

How do I calculate the capacitor value (Farad & Voltage) given the pulse current, pulse duration & maximum tolerable voltage drop?

I have an electronic component with following characteristics: Operating voltage: 4.5V Peak operating current: 2000mA for 600uS every 4000uS. The device can ...
3
votes
3answers
221 views

Automatic Capacitor Charge/Discharge Circuit

I am still somewhat of a beginner in electronics, so please go easy on me, but here is a situation I have encountered, and hopefully some of you have as well. I have a voltage source of 5volts, but ...
4
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1answer
79 views

Why does capacitor value changes when capacitor is DC biased?

I have seen ceramic capacitor value varying under various DC biased levels. Dc biased was a huge factor as capacitor value is reduced by 50% almost? Why?
1
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1answer
46 views

Can an electrostatic loudspeaker be considered as a capacitor?

A basic capacitor works as two parallel plates carrying opposite charges and have an electrostatic force holding the charges in place (without making any contact); can't an electrostatic loudspeaker ...
1
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1answer
89 views

How internal capacitor stud finders work?

I don't understand how can a non magnetic object like wood be detected using a stud finder For instance, stud finders find wood from dielectric constance, but I don't understand the princible. The ...
0
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4answers
113 views

Circuit capacitance question

Given the following circuit, what ways there are to calculate its total capacitance? Thing is this is not a simple case, and I can't really decide which part is parallel and which is a series, ...
1
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1answer
72 views

Voltage level too low for MAX232

I'm trying to connect TI's MAX232 to my Arduino so that I can communicate with my PC. I have connected it exactly as the picture shows: Tx/Rx are not connected because I just wanted to see if I can ...
2
votes
1answer
86 views

How to measure ESR

I have a bunch of capacitors but no clue of what ESR they have. Is there a way to measure the ESR? Can I set up a test circuit to measure it?
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0answers
39 views

Paired Polarized Electrolytic Capacitor to Form Non-Polarized [duplicate]

A quickie... I needed a 1uf non polarised cap for a circuit which I didn't have so I found info that said I could join the + of two polarised caps and connect the two - terminals into the circuit to ...
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0answers
15 views

Dell u2311h Monitor gone bad, which capacitors do I replace? [migrated]

I have 3 u2311h monitors in an eyefinity setup. For aesthetic purposes, I do not want to replace the faulty one with a newer u2312hm. The problem with the faulty one is as follows: For the past few ...
1
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1answer
196 views

Do the capacitors on the picture look broken?

I have here a CD player's board (the player is from 80s, Gründig CD 30), the player works OK first 10 seconds, after that there is loud noise (sound is still possible to recognize but is very very ...
0
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2answers
118 views

Schematic Diagram of the circuit

I would like to know what will happen in the circuit diagram below when the switch is on( connected to a voltage source and R1) and switch off(connected to the R2) My thoughts... For switch on only ...
3
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3answers
150 views

Using 555 to generate square signal with fixed duty cycle / variable frequency

I am attempting to design a circuit whose output is a square wave with the following properties: Fixed duty cycle, as high as possible (let's say 99%) Variable frequency, between 0.2 - 20 Hz (I'm ...
2
votes
3answers
170 views

Could this white paste be the cause of intermittent power in a Dell LCD board? [closed]

I took apart my Dell 17" to try to repair it. I expected a burned out capacitor or something else obvious but the only thing I found was this white paste touching several components. Could this be the ...
7
votes
3answers
639 views

What happens when plates of a fully charged capacitor are isolated from each other?

I'm a mechanical engineering student and I'm working on a project that involves a high voltage capacitor. I understand that when the separation between the plates of a charged capacitor is ...
2
votes
2answers
85 views

+/- 60V Sawtooth/Triangle/Sine Wave

I'm trying to create a power supply for biasing a Langmuir probe. It needs to run some sort of predictable wave (I need to compute an I-V curve for a plasma, so I need to vary the voltage in a ...
3
votes
1answer
57 views

What effects might an electrolyte leak have on nearby electronic components?

If an electrolytic capacitor were to leak electrolyte on nearby circuit boards, what might the effects be? Short-circuits? Altered impedances? Are there caustic effects? Or is it possible to ...
8
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2answers
287 views

Should ventless electrolytic capacitors be mounted upside down?

I understand that electrolytic capacitors with vents should not be mounted upside-down. I read that the vent may not function properly and the electrolyte may leak out. Smaller electrolytic ...
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2answers
70 views

Capacitor voltage in a 555 timer circuit

If I change a 10V capacitor in a timer circuit with a 16V capacitor, will the circuit turn on longer?
2
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0answers
91 views

Eliminate/reduce speaker pop when powering off amp [closed]

I'm repairing an old 1970's record player and one of the items on my list is to try and reduce the loud 'pop' noise when switching off the amp. I've done a little research and it seems there are a few ...
0
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0answers
20 views

Troubleshooting my antenna power delay

Awhile ago I build a circuit to fool my power antenna into sensing a constant voltage while I started my car. enter link description here It worked great. So installed a new power antenna and ...
4
votes
2answers
252 views

What is the purpose of the Motor Run Capacitor?

Looking at a control box for a marine Air Conditioner and it has a HUGE capacitor in it. The schematics label it a "Motor Run Capacitor", but I always thought it was just used to start the motor. ...
-3
votes
1answer
38 views

impact of inductor and capacitor at resonance [closed]

It is said that inductor and capacitor cancle each others effect during resonance bt do they still have any effect on the circuit??
4
votes
1answer
364 views

Voltage divider using capacitors

A test circuit requires to generate 1V (50Hz, sine) using a voltage divider made of capacitors. Simulation of the circuit using two identical ceramics capacitors (±5%) gives half of the input voltage ...
0
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0answers
62 views

Gate capacitance in CMOS

Gate capacitance in an N-MOS consists of gate to body capacitance + gate to source capacitance + gate to drain capacitance. Now how does each component of this gate capacitance vary with different ...
3
votes
1answer
110 views

What standard governs the dimensions of SMT chip resistors and capacitors?

I am aware of the JEDEC registered outlines, which define the standard mechanical dimensions and tolerances for a wide variety of solid-state packages. However, these standards do not appear to cover ...
7
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1answer
209 views

Help me modernize this audio circuit

When I was a kid, I built this circuit. You hook up a small capacitor to the test leads or maybe a couple in parallel and the speaker will output a different pitch based on the test capacitance. I ...