New answers tagged capacitor
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How can you calculate Peak Pulse Power for a Non-Rectangular Power Pulse
This is something of a non-answer, alas; but also the best possible answer?
That's a bit contradictory, so let me explain.
When the resistor is thermally limited, the problem is to avoid exceeding ...
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Building a hybrid ultra-capacitor and battery bank
There are hybrid supercapacitors to combine some of the advantages of both in one module.
But for a system with both battery and supercap a very a basic arrangement could be something like this:
It ...
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How can you calculate Peak Pulse Power for a Non-Rectangular Power Pulse
The same document explains this on item 4:
So, you need to write the voltage's equation and solve the energy integral:
$$
E = \int_{T1}^{T2}p(t) \ dt
$$
If you have \$p(t)\$ put it directly. If you ...
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Should I connect a small DC motor directly to the mains without an isolation barrier?
Do NOT do what you are suggesting!
You are planning to connect uninsulated motors, to the mains, with no safety barrier or protection. This is extremely dangerous.
12V & 24V power supplies, ...
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Sequential diode and capacitor - low vs high capacitance
Your diode has additional properties that can typically be ignored in most cases, notably, reverse recovery time and reverse leakage (frequency real slow, output capacitance real high, respectively). ...
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Why is it OK to separate a circuit in the process of simplifying it?
Placing a constant voltage source from one node to another isolates (decouples) all branches connected to the nodes from each other.
Because the voltage across each branch is known, each can be ...
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What is the role of an MKP capacitor in the input of this SMPS? What happens if I remove it?
For reference, a typical schematic can be found on page 13 of this datasheet (similar but unrelated part); or on numerous appnotes, or schematic collection sites.
https://www.onsemi.com/download/data-...
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What is the role of an MKP capacitor in the input of this SMPS? What happens if I remove it?
That's an X2-rated capacitor. Those are intended to die by shorting (and in that way taking out a fuse), so you should check its resistance to see whether that is what it did.
They usually buffer ...
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Need help with capacitor code
The Manufacturers Logo is International Rectifier, who's products are now part of Infineon.
From the attached picture the part number is FS300<last character unreadable>. Are you able to get a ...
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DTR pin in the FT232RL working confusion
The reset pin of the ATMEGA328 is special. It can tolerate up to 13V. It can be used to enter the high-voltage programming mode although that is not triggered in this application.
See the Absolute ...
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Capacitor taping Vs straight leads
From Panasonic Packing specifications
With taping means that the leads have outside bend in order to increase the pitch between them?
Not directly. E13 (second row) has the same diameter (ø8) and ...
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Using a potentiometer to adjust a capacitor voltage
This does what you appear to want.
Note that you can acieve the same result by simply connecting the capacitor to the potentiometer wiper directly - however, for many capacitor values that will take a ...
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Circuit explanation with short circuit and independent current source
The 5 Ω resistor is shorted out hence, there will be zero current flowing through it.
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In a DC circuit with a battery and a capacitor how do electrons on the capacitor plate connected to positve terminal flow?
The negative plate of the capacitor is connected to the negative terminal of the battery and, the battery negative is a fairly unlimited source of electrons.
So, electrons "gather" at the ...
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In a DC circuit with a battery and a capacitor how do electrons on the capacitor plate connected to positve terminal flow?
You forgot the electric field inside the capacitor.
The voltage source puts more electrons on the negative plate of the capactor and sucks some from the positive plate. This process stops once the ...
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State space model of third order circuit
Rewriting your system of equations in matrix form yields
$$ T\cdot \dot{x} = A\cdot x + B\cdot V_{in}$$
where \$x\$ is the state vector and \$T, A, B\$ are matrices of appropiate dimensions. Assuming ...
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3-way switch with self-resetting toggle switches
What you need is an 'impulse' or 'ratchet' relay that changes state with a pulse input to its coil and reverts on the subsequent pulse.
In other words, it changes state on consecutive pulse inputs to ...
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3-way switch with self-resetting toggle switches
This should only be a problem if you can’t see if the lights are on or off from where the switches are.
You can buy three way switches with indicator lamps that will tell you if the circuit is on or ...
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Find a matching interference suppression capacitor
Values can be within a fairly wide tolerance; 2400pF is no problem. The current rating however must meet or exceed, which rules out #1.
There should be an inductor in there also (hence the current ...
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Why don't oppositely charged ends of separate batteries and capacitors produce current flow?
Current flows in circuits, closed loops. You are showing two open-circuit scenarios. Keep in mind, voltage is a potential difference between two points in circuit. The potential is across the battery. ...
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Why don't oppositely charged ends of separate batteries and capacitors produce current flow?
Current requires a closed circuit to flow.
If you have a single battery connected to nowhere, no current flows.
If you have a single battery connected to anywhere with one wire only, be it a load or ...
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Smoothing Capacitor value?
Load Current: 7A Frequency: 120Hz Ripple Voltage: 15V
The ripple voltage in the equation from the web calculator you used
$$C = \frac{I_{load}}{f \times V_{ripple}}$$
is "the peak-to-peak ...
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Smoothing Capacitor value?
As a rule of thumb, 1000 uF per amp, so you would want at least 7000 uF.
You could come up with an approximation using constant current discharging a capacitor, i.e. \$ \Delta V = {i \ t \over C} \$ ...
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Is my washing machine board bad?
As others have said, those two cracked capacitors are bad and you should replace them with the same or higher voltage and capacitance rated caps.
For example, the 470uF/35V can be replaced with 470uF ...
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Is my washing machine board bad?
Yes, those two caps (top left and the brown-ish one in the middle) are definitely defective. These types of electrolytic capacitors tend to fail in this way (crack open) after years of use.
If you're ...
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Is my washing machine board bad?
Yes, it's bad, due to bulging caps with electrolyte leaking out.
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2A223J fixed capacitor immediately shows OL on resistance test
Resistances tend to be measured with limited current. If the current is near constant, voltage (and thus displayed resistance) will rise linearly in time, at a rate inversely proportional to the ...
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E series Components and Information
Resistors and capacitors are commonly given values according to an E series, as are inductors and zener diodes.
Resistors can easily be made and are often required to percent tolerances, so all values ...
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E series Components and Information
There is a huge amount of information available on the E "preferred values" scheme available from a simple web search. Wikipedia has a very good article.
The scheme defines spacings based ...
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How can I find the steady state of current I with sinusoidal voltage source?
I'm looking at the book problem in the 9th edition right now:
What they want you to think about is \$I=\frac{125\:\angle -60^\circ}{\mid Z\mid\:\angle \theta}=\frac{125}{\mid Z\mid}\:\angle\left(-60^\...
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How can I find the steady state of current I with sinusoidal voltage source?
You lose me a bit with the notation convention you're using in the line that start with "Now I=..."
I believe if we use exponential form for the phasors (\$Ae^{j \theta}\$), everything will ...
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Measuring capacitance with NE555 in astable mode
This is an oscillator, so you measure capacitance by measuring the frequency and then using the formula in NE555's datasheet or an online 555 timer calculator.
A precharged capacitor within voltage ...
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Transient response of capacitor connected to current source with no resistor
Well, the voltage- and current relation in a capacitor is given by:
$$\text{I}_\text{C}\left(t\right)=\text{V}_\text{C}'\left(t\right)\text{C}\tag1$$
So, when \$\displaystyle\text{I}_\text{C}\left(t\...
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Can I increase a capacitor's working voltage by putting two capacitors in series and doubling the uF value? I am dealing with a 0.1uf rated @1700VDC
I'm not totally sure from your question if you need a 0.1µF capacitor rated for 1700VDC, or a 0.2uF rated for 1700VDC.
If it is 0.1uF, I found 3 on digikey
(nb : make sure they meet all your ...
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Can I increase a capacitor's working voltage by putting two capacitors in series and doubling the uF value? I am dealing with a 0.1uf rated @1700VDC
To a first order yes, but depending on style of capacitors you might need resistors to balance the voltages.
Most film caps fine, but uneven leakage on electrolytic capacitors make stacking without ...
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Derating of C0G DC block capacitors with applied DC voltage
C0G/NP0 do not need derating due to voltage.
C0G compared against other MLCC like the X7R, do barely dissipate any energy in AC mode in comparision.
I've used C0G in 1000V boost converter to snub the ...
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Transient response of capacitor connected to current source with no resistor
Start with the integral equation. The voltage across a capacitor is equal to the integral of the current as a function of time. If the current is a constant, it falls out of the integral. That ...
- 17.1k
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Transient response of capacitor connected to current source with no resistor
A capacitor that is fed with a constant current will experience a constant voltage rise.
$$\frac{dV}{dt}=\frac{I}{C}$$
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Derating of C0G DC block capacitors with applied DC voltage
There are two significant misconceptions from your colleague:
Type 2 dielectrics, in general, need voltage derating, or some [fixed] ratio thereof.
All ceramic capacitors, in general, need derating.
...
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Derating of C0G DC block capacitors with applied DC voltage
C0G and in general class 1 dielectric ceramic capacitors don't derate neither with temperature not bias voltage, class 2 on the other hand do, the lower the number of that dielectric the higher the ...
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Derating of C0G DC block capacitors with applied DC voltage
Murata says in their ceramic cap FAQ that C0G caps have no DC bias characteristics.
So either the caps need to be derated for other reasons, but at least they don't need derating due to capacitance ...
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Why are charge pumps only used for low current applications?
at least for low quantities, I need to do some calculations, buy specific cores and wires and wind the wire around the core myself. It's very time consuming.
Instead, see what suitable fixed ...
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Why are charge pumps only used for low current applications?
As pointed out in the comments of this answer, switched capacitor DC-DC converters, such as one built around an LTC7820, can be extremely efficient (99% efficiency claimed in that datasheet) and can ...
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Discharging one side of a capacitor?
A capacitor is a device designed to contain a net zero charge by producing a very low energy electric field for a given charge difference. This is done by making the extent of the field very small ...
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Capacitor at output of component followed by capacitor at input of another component
If you put them very close you can share the capacitor between them. Use whichever value capacitor is larger. However, if you're worried about noise to the point where you cascade an LDO after a ...
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What could these mystery XX capacitor values in this schematic denote?
These are bypass capacitors (it says so at the top). usually this is not a critical choice. Find the data sheet for whatever parts are closes to the capacitors and see what value they recommend.
100nF ...
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What could these mystery XX capacitor values in this schematic denote?
It could denote anything.
It could mean they are capacitors drawn just in case they are needed, and the circuit was determined not to need these caps so they can be left out from the circuit. So it ...
- 130k
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Capacitor and LDO voltage regulator gets really hot on circuit board
In addition to what the others said, I'll use another LDO (LDL1117) as an example.
Thermal resistance junction to ambient is very high, this is the value to use for a layout like yours. However ...
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Capacitor and LDO voltage regulator gets really hot on circuit board
@Spehro Pefhany probably found the problem.
I just wanted to complete on your thermal calculations.
You say (I haven't checked the datasheet myself) :
R_th = 120°C/W
P = 0.912W
However, in your ...
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Capacitor and LDO voltage regulator gets really hot on circuit board
Looks like C1 is shorted, which is shorting out your 3.3V rail and causing the regulator to current-limit.
Other pins on the chip appear to be shorted as well. Please inspect the board carefully for ...
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