Capacitance is the ability of a body to store an electrical charge

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What is power dissipation capacitance?

This question is derived from the answer to another question What is the input current of the 74HC595 The answer makes a note to the OP, that he should also consider power dissipation capacitance. ...
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35 views

How to switch on or off capacitance on a piece of conducting material?

I don't know if this is the right way of describing it, but I need to activate an area of capacitance on a touchscreen by applying some current to a piece of conducting material like tinfoil. I am ...
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85 views

Two capacitors charged separately and connected in series. What will be final voltage? [on hold]

Please look at the following link before reading my question. What happens to the capacitance of a system if capacitors are charged in parallel and then put into a series circiut It is explained ...
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2answers
57 views

Understanding to isolating sensor input capacitance

The circuit given above is pH sensor buffer circuit, picture taken from here. This circuit have pH sensor input and gives an output that can be read by multimeter which is U2's OUT_ pin . U1 is here ...
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76 views

How to calculate a electrolytic capacitor based on current and voltage to have the smallest ripple

I have built a circuit involving LEDs powered on 230V AC. The LED current driver that is powered on 30V and contains 10 LEDs of 1W each. 10 of these modules are linked in series and are ...
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34 views

Temperature Coefficient of Capacitance

How can I find the Temperature Coefficient of Capacitance of the following capacitor series: http://www.cde.com/resources/catalogs/TAS.pdf
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37 views

Why does putting capacitors in a series reduces their overall capacitance? [duplicate]

I'm new to electronics and would like to learn. I can't wrap my mind around why this is so.
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1answer
59 views

factors influencing capacitance of a cable

I am out of my depth here so I am looking for a simple explanation. If you have twisted pair cables of differing makeup, varying in conductive material, diameter of the conductor, number of twists per ...
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1answer
92 views

An “operation” game sensor where the stylus is NOT attached to the power source

Edit: The person operating the catheter will be wearing latex gloves. The only human tissue the catheter would touch would be that of the patient. Also, to clear up some confusion about what exactly ...
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67 views

help with capacitors and project

Capacitors have me crazy. I cant comprehend them even after lots of research. I know that capacitors deal with resistance, voltage, current and capacitance.(ohms, volts, amps and farad) but I cant ...
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48 views

Calculating capacitance at resonance

Could someone help me please asap, New to this ! Thank you! working out for the first one , could someone confirm? first question has been confirmed thanks Second question confirmation? thanks
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2answers
52 views

How to programatically simulate a click on a capacitance-sensitive button?

I am tearing apart a SONY HT-XT1, which has capacitive buttons to put it in a different case for a project: I've taken it apart already and am now met with a motherboard with 3 pads on it. Touch ...
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1answer
95 views

Did Capacitative Loading Kill My Op Amp?

I've been playing with various constant current source configurations to help control the current output of my bench power supply and my latest efforts centred around the op amp and MOSFET approach. ...
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13answers
20k views

Measuring feline capacitance

When I pet my cat, and then touch her on the nose, I get a little shock. Sometimes, when she walks up to something, her nose sparks and she jumps back and puffs out. I was wondering how I might go ...
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1answer
78 views

What is the capacitance and/or inductance of a single straight piece of copper wire?

What is the capacitance and/or inductance of a single straight piece of copper wire? I know the answer is on Wiki, but I need for the answer to be supported. I know that Wiki provides references, ...
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0answers
38 views

Using capacitors to control the speed of a relay loop

Background: In my autoshop class at school we are required to make a circuit that uses relays. When one relay comes on the other one shuts off and it creates a loop in which they switch really ...
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2answers
55 views

Big capacitors measurement(LCR meter related)

I digged up some capacitors from amplifier and decided to test them, one of them is said to be 8200 uF, the other 4700 uF. I measured them with LCR meter and it gives very strange numbers. If LCR ...
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4answers
134 views

Capacity of a capacitor fully charged vs half charged

I read in most places, when people ask "can I replace a 10v 10uf with 100v 10uf?" and everybody answers "it's the same". Well... how can it be!?, I have a comparator circuit, that uses a little ...
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1answer
48 views

Need help with Relaxation Oscillator with Parasitic Capacitance

I am trying to build a capacitance meter using a simple relaxation oscillator with a fixed resistor R in series with a capacitor to be measured C. I am applying the formula where Freq=frequency and K ...
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3answers
129 views

Output capabilities of super capacitor

I have come across a question that is very near and dear to my heart and I am in the hopes that somebody can answer this new years eve question of mine per se. So I am wondering, if I were to run ...
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1answer
73 views

DC/DC converter/eFuse maximum output capacitance

I have some doubts about the design of this DC/DC converter circuit/PCB circuit: On the left side there is a 400V to 12V DC/DC converter (Vicorpower DC/DC Mini, 300W). The maximum output ...
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1answer
159 views

Why is the capacitance changing while measuring?

I have 2 different 100nF capacitors. Let's call them A and B. My dad told me that B is "better" than A. I've tried measuring their capacitance using a Metex multimeter which has the option of ...
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1answer
58 views

ACS758KCB Wiring Diagram

I am using the ACS758KCB Hall Effect sensor for a project. On the front page of the Datasheet it list a .1uF capacitor between Vcc and GND, in addition it lists a capacitor, Cf, between GND and ...
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1answer
48 views

Capacitance value - AC RC Circuit - Impedance Method

Here is the circuit: simulate this circuit – Schematic created using CircuitLab \$ V_i = \frac{8}{\sqrt 2} \angle0° V\\ V_c = \frac{6}{\sqrt 2} \angle45° V\\ R = 1000\space\Omega \$ ...
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2answers
97 views

How to select capacitor for my rectifier circuit

I had designed a rectifier circuit, in that I don't know how to choose capacitor. for example if I'm get in input supply as 9 V, now I want change it for 10 V, then how should I choose capacitor.
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34 views

Capacitor Units For Power Factor Correction

I have got the assignment to improve power factor of an industry. I have worked it out and found capacitance in K Vars and Micro Farads but need to know about the capacitor representation in volts?
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1answer
355 views

Crystal Oscillator not giving correct frequency

I have a 48MHz Crystal Oscillator (see here) that I am using as a clock for my microcontroller (EFM32GG332F1024). Looking at the datasheet for this crystal it seemed to me that the load capacitance is ...
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1answer
70 views

How is a reed switch used to charge/discharge a capacitor?

Ok, so there's no way to disguise this; I admit this is a question I've been set for homework but I can't find a full answer to. I know that, in brief, a reed switch consists of two metal contacts ...
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1answer
37 views

Capacitor with n electrodes

In my book it says that the capacitance in a capacitor with n electrodes is (n-1)*Co, Co is a capacitance of a two parallel plates capacitor. I know how to distribute charge when there are 3 parallel ...
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2answers
411 views

Does current flow stop when a capacitor is fully charged?

If I take a 1V battery and a 1 farad capacitor and a bulb and connect them in a circuit. Then will after the capacitor gets charged (not fully charged as that is impossible) will the bulb gradually ...
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89 views

Self tuning 125khz RFID reader

I have a RFID reader based on the EM4095 IC. I would like to make the reader self-tuning so it can handle varying inductance in the antenna due to reading tags near metal. I had thought of using a ...
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2answers
117 views

Capacitance - Voltage characteristic diagram in a Schottky diode

I 've searched the web for that diagram with no satisfactory result. Does a schottky diode has capacitance or not because of very tiny depletion (almost none) zone ?
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1answer
66 views

Do we ever use the pin capacitance of a digital circuit component (e.g ASIC, FPGA) in doing timing or data integrity analysis

As far as I understand, the pin capacitance on say an ASIC or FPGA effects the rise and fall time of the signal on it. It is also possible that the impedance offered by this capacitance to a very high ...
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2answers
521 views

How to make LC tank circuits oscillate continuously?

An LC tank circuit produces oscillations, when the capacitor is charged and connected to the inductor, but the oscillations decay gradually. How to make it continue, i.e. oscillate continuously? I ...
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82 views

How long of a wire and how big of a load can I have for SPI bus?

I have a system where I will connect up to 128 identical magnometer ICs up to an FPGA. I am trying to decide between SPI and I2C for comms. If I use SPI the setup will require 128 + 3 wires IF all ...
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97 views

Finding the value of capacitance for a given circuit

How would you know how much capacitance you should use in your circuit or is there any formula to compute on the desired capacitance you should use on your circuit? I have this circuit (figure shown ...
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1answer
60 views

Where does the power absorbed of this capacitor come from?

In my circuits book, the voltage across a capacitor is given as \$v(t)=100\cos({2\pi60t})\$. Because \$i_{ab}=C\frac{d}{dt}v_{ab}\$, we naturally compute the current as ...
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482 views

What happens to the capacitance of a system if capacitors are charged in parallel and then put into a series circiut

If you have 2 capacitors 2V, 2F each. When you charge them in parallel, the system will have 2V and 4F when you attach a load to it. If you take the charged capacitors and then put them in series, ...
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3answers
253 views

What does an inductor's current stabilize to in DC?

As you can see from the below graph, after an inductor is turned on, the current is stabilized to approximately 6.5mA. My question is: what does the 6.5mA represent? Where did that number come from? ...
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90 views

What's the definition of “signal to ground capacitance” of a coaxial cable? What's the difference between it and normal capacitance?

What is the definition of "signal to ground capacitance" of a coaxial cable. I know what capacitance is, but I'm not sure whether it is just the same thing.
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1answer
96 views

Application of charge conservation

I don't know how to start formulating equations or finding equations for this circuit, I have to prove this by mathematical equation. My adviser told me by charge conservation but I don't know how to. ...
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54 views

Charge conservation

How can I apply the theory of charge conservation for this charge pump circuit. Specifically on the pump circuit. How do I get the charges on the capacitors?
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387 views

How to design an square wave Oscillator Circuit with 1-20 MHz range?

I need a circuit that will generate square waves in a range of 1 to 20MHz. The circuit also should be adjustable in a scale of 0.05MHz for each step. There is no need for adjustments during the ...
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50 views

Diffusion capacitance

As far as I know, capacitance is created by two conductive plate with an insulation between them as they can store charges. When a diode is in reverse bias, it shows a capacitance because the n and p ...
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1answer
266 views

Solid State Relay Capacitance Bad for Audio?

Regarding MOSFET optocoupler relays like the Panasonic AQW212, am I correct in understanding that the capcitance between the terminals and ground when the switch is open ("off") is around 100pF when ...
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1answer
247 views

What is the role of the capacitor within the assembly

I have some questions regarding my assembly and especially on the role of the capacitor within the circuit. Before I added the capacitor I encountered 2 issues: when the piezo was squeezed (a ...
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1answer
123 views

Minimum number of capacitors

I require a capacitance of 2×10^-6 F in a circuit across a potential difference of 1kV . I have a large number of 1×10^-6 F is available which can each withstand a potential of 400V. Suggest a ...
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1answer
247 views

how to select capacitor for a crystal oscillator

Here is a 32 MHz crystal from one of TI's reference design The BOM list defines the crystal as ...
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139 views

Dielectric can be insulators?

People say that dielectric should be an insulator so that it can decrease net electric field increasing capacitance.. My question is if the object is a insulator how does the object get polarized ...
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1answer
407 views

What capacitors do when it is connected in Series and parallel to a AC input

I have seen in many circuits the capacitors are connected in series and parallel with the AC line. What the capacitor actually does when it is in series and parallel. I know capacitors passes AC ...