New answers tagged voltage
2
votes
Accepted
5V input tolerance on ATF16LV8
the DC characteristics "input high voltage" is the voltage range at which an input counts as "high".
The fact that the device doesn't get inherently damaged at some input voltage ...
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Why do I measure a different voltage across an LED when I measure the two terminals with my multimeter vs when measuring everything related to GND?
Here is one possibility:
simulate this circuit – Schematic created using CircuitLab
VM1 measures V1 minus the LED drop at the meter current. The LED may glow faintly, but enough to be visible ...
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What do multiple volts mean?
To better understand this, let's think about what voltage actually IS. Voltage comes from volt, which is the unit of Electric Potential. The electric potential of a point in space is the electric ...
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What do multiple volts mean?
How much of joules of energy a coulomb of charge is experiencing anywhere is that much volts.
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What do multiple volts mean?
Neither.
2 joules of work is done in moving 1 coulomb of charge through a potential difference of 2 volts.
More generally:
\$U\$ joules of work is done in moving 1 coulomb of charge through a ...
- 47k
9
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What do multiple volts mean?
Neither.
As C*V=J, the following applies:
1J means 2 coulombs and half a volt.
1J means half a coulomb and 2 volts.
2J means 2 coulombs and 1 volt.
2J means 1 coulomb and 2 volts.
- 172k
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What do multiple volts mean?
The equation relating these three units is
joules = volts × coulombs.
So just substitute those numbers in and it is clear which is correct.
xJ = 2V × 1C -> xJ = 2J -> x = 2
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Using a capacitor to mitigate voltage drop
I suspect the trips are caused by the heater resistance being too low when it is cold. If that is the case, then try a "soft-start" circuit connected in series with heater that limits the ...
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2.5A 250V power cord for a laptop
It's a laptop adaptor. Read the specifications on the back -- it says that the input power requirement is 100-240V, 1.8A.
When she hits the US, she just needs to get a power cord that'll fit the ...
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2.5A 250V power cord for a laptop
This charger can handle both Brazilian 220V/60Hz and US 110V/60Hz. As well as European 230V/50Hz.
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Finding capacitor voltage in this seemingly simple rectifier circuit
This answer might not be what you are expecting, but I think the concept is very useful. It's based on a previous answer of mine found here:
What is the relation between NE555 voltage doubler output ...
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Finding capacitor voltage in this seemingly simple rectifier circuit
There is an analytical approach, but it is not simple.
The capacitor voltage will stabilize at a value for which the charge into the capacitor during a cycle equals the charge out. This is complicated ...
- 178k
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Finding capacitor voltage in this seemingly simple rectifier circuit
Update:
There is no simple formula for the Vdc out as this is a nonlinear circuit. I recall our Hammond power supply designer circa the mid-80s having elegant nomographs for all these and similar ...
- 148k
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Full Bridge Rectifier - Output Voltage Saturation
Use a battery powered oscilloscope as the one of the easiest ways to "float" the oscilloscope. Or use a transformer as the source for the rectifier.
You are fortunate that you used a signal ...
2
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Full Bridge Rectifier - Output Voltage Saturation
Yes like I suspected, the diodes are in wrong polarity.
The electrolytic capacitors do not handle negative polarity well and will leak current, sometimes very heavily, in reverse direction.
The 50 ohm ...
- 172k
2
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Full Bridge Rectifier - Output Voltage Saturation
Can you please elaborate on the "short out one diode"
If the scope and signal generator share a ground, this happens even if you don't measure input and output at the same time:
All ...
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What is the easiest way to turn 1 kV DC to 10 kV DC?
Separate the drops by a larger distance before discharging them.
maybe using some sort of hydrophobic ramp
The drops carry charge, so the further you separate them the more room the is to generate ...
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Is there any component that opens or closes at the exact defined or set voltage?
Check out, for example, the LM185/285/385 family of fixed and adjustable pseudo-zener-diodes.
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Is there any component that opens or closes at the exact defined or set voltage?
Depending on what you are really after, it may need a whole circuit with multiple components to do what you want.
For example a comparator can be used to have an output depending on how two monitored ...
- 172k
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Is a secondary resistance of 1.2 ohm OK in an inverter?
The part that looks like a capacitor isn't a capacitor. It is a metal oxide varistor (MOV.) MOVs often fail short circuit.
An MOV would be installed where the AC power comes into the device. That ...
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How does an autotransformer change voltage if primary and secondary share the same wire?
Here, for example (image from here) is a step-up autotransformer:
There are more turns around the magnetic core between the high side of the source and the output load (on top of the primary winding) ...
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How does an autotransformer change voltage if primary and secondary share the same wire?
An autotransformer does indeed have a single winding, but that winding has three connection points - one at each end of the winding, and one somewhere in the middle.
simulate this circuit – ...
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How does a voltage transformer work under load?
Under load, the secondary winding current creates its own flux,
directed against the magnetizing flux.
Not really; consider the situation of the secondary load beings resistive. Then the secondary ...
- 473k
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How does a voltage transformer work under load?
It occurs across the primary winding’s leakage impedance as the increased primary current under load causes greater voltage drops across the winding’s resistance and leakage reactance, so although the ...
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How does a voltage transformer work under load?
The primary voltage drop is to generate the flux that counters the flux from the secondary current.
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Voltage Divider wrong result - EasyEda
It looks like EasyEda is not liking the capital K at the lower resistor. If you calculate it for 6.8 Ohm, the voltage divider should give ~3.8 mV.
- 9,639
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Idea on how to absorb voltage spikes
To limit the peak current you can place an inductor in series with the magneto.
To use both polarities of the magneto, you can use a capacitive coupled rectifier and get some unregulated DC voltage ...
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Idea on how to absorb voltage spikes
Obvious thing to try is a full wave bridge rectifier-> capacitor-> buck converter. But you might need to add a shunt limiter (TVS, power Zener etc.) so the voltage does not go sky-high when the ...
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Idea on how to absorb voltage spikes
Try this circuit:
simulate this circuit – Schematic created using CircuitLab
The values aren't critical and you can make adjustments as needed. If you need higher efficiency, you can put a ...
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Charge pump with MOS-error-amplifier, please help me understand this circuit
I am going to quote a few lines of the Design of CMOS Phase-Locked Loops by Behzad Razavi:
"Charge pumps suffer from numerous undesirable effects, contributing both ripple and noise ... The ...
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Battery discharge over time
Unfortunately, estimating remaining charge left in a battery or cell is not as simple as monitoring the fuel level in a liquid fuel tank. A battery's voltage remains close to nominal voltage during ...
- 180k
1
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Accepted
Headlight burnout
If a recall was issued it should still be possible to purchase the repair part, even if you no longer qualify for free service.
Check that the alternator wire is intact.
- 36.4k
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What happens when base voltage is higher than the collector voltage in a bipolar NPN transistor?
As mentioned in other answers, if the base voltage is higher than the collector voltage (for an NPN transistor) and the base voltage is also higher than the emitter voltage, the transistor is in ...
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What is this 6-pin SMD IC marked IV7NM?
It is a MP2451DT Step down converter from MPS.
"V7" is the significant marking, the vertical bar in the left is pin 1 indication.
Picture from lcsc:
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What is the best way to convert a 1.2-4.5 vdc signal to a 0-5 vdc signal?
As already mentioned by @Velvet, you need to subtract 1.2V and then you need to add some gain.
Something like below can do the job.
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What is the best way to convert a 1.2-4.5 vdc signal to a 0-5 vdc signal?
What supply voltage do you have available? If just 5V you need to use a rail-to-rail op-amp. If higher like 12V you can use a common op-amp.
Btw, you need to decrease the signal -0.35V first, then ...
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