New answers tagged current
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Converting an NO reed switch to a NC with lowest leakage current
You probably no longer need an answer to your question, but for the sake of posterity, and because your question is one of the top search results for "Convert read switch..", I'll give my ...
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Problem 3.15 from Hyat: Engineering Circuit Analysis
The two independent current generators and the two resistors are all in parallel. That is, the four bipoles have only two nodes in common, the upper one and the lower one. The two independent current ...
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Problem 3.15 from Hyat: Engineering Circuit Analysis
You can assign your current reference directions any way you want. Depending on the reference direction you pick the result may have the opposite sign of the original method, but the magnitudes of the ...
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Current Consumption of multiplexed 7 segment
You need enough average current per 'on' segment for it to be adequately bright. So if you have 4 digits multiplexed you'd need around 4x the current for a single digit that is driven statically.
The ...
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Current Consumption of multiplexed 7 segment
Is the current that the regulator must supply the same for both modes?
and
Does it mean that whether it provides for one or for matrixed segment
is the same?
Theoretically yes; in practice it's a ...
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How can I implement current control for proportional valves?
The 16-mm valve recommended PWM frequency is 1000 Hz; the 22-mm valve is 500 Hz.
Your circuit has just a few issues: An LM358 performs poorly going in and out of saturation, and even with an "...
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Can you touch a live wire without being shocked?
In theory, if you're insulated, no current will flow if you touch a live wire.
In practice things aren't so simple. That insulation, be it rubber boots, rubber mat, or some other non-conductive ...
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Accepted
Relationship Between Current and Power in a Refrigerator
"Defrost Amps: 4.4" means that up to 4.4A are used by the defrost heater, which is a separate thing from the compressor.
7.7A - 4.4A = 3.3A.
3.3A * 115V = 379W, which is quite a nice match ...
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What is the difference between a rectifier/signal diode and a Zener diode?
Fundamentally, they are optimized for different operating modes.
Both types of diodes you mention here are a junction between two differently doped types of semiconductor. The doping profiles are ...
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What is the difference between a rectifier/signal diode and a Zener diode?
The rectifier diode and the Zener diode are both types of semiconductor diodes, but they serve different functions in electronic circuits.
Rectifier Diode
Function: Rectifier diodes are primarily used ...
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MOSFET gate driver current requirement for 2000 volt MOSFET
As per the data sheet of the MOSFET, the test condition is given at gate resistor 2 ohm and Vgs change as (18-(-2))=20V. So, as per this, the peak gate current requirement is 10 Amp.
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Why does disconnecting the receiving end of a transmission from the sending end increase the voltage at the receiving end?
Why does the voltage increase when the circuit is opened, but then decrease after 544us but not after 272us?
The voltage increases when the circuit is opened, because of the inductance of the wire. ...
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Reverse current into DC/DC or LDO
A generic regulator only sources current, and will source curtent to keep the output voltage at the setpoint. They do not, generally, sink current to bring voltage down to the setpoint.
So if your ...
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Does mobile charger and buck converter have any basic difference?
Does mobile charger and buck converter have any basic difference?
A mobile charger is typically a (fairly) isolated power supply, while a buck converter typically shates it's input and output grounds....
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Accepted
Using two supply rails (on supply and output pins) with 74HC595
That's not a good way of doing it.
This is even said in the data sheet; outputs should not be pulled above VCC, and 70mA total current should not be exceeded, and you are doing both.
If 5V supply ...
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Using two supply rails (on supply and output pins) with 74HC595
Just a first note: You are not connecting 5V supply to the SR output pins, there are the resistors and LEDs in series. These limit the clamp current to \$I_{OK} = {(V_{Supply} - V_{f} - V_{OH}) \over ...
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How to vary output current by maintaining constant output voltage?
Not unless you can change the valve's impedance as well.
From Ohm's Law we have Z = E / I, if voltage E is constant and current I changes then impedance Z must also change.
Edit: Now that you've added ...
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Dual N/P-Channel MOSFET Dies with Smoke
When Q1 turns off, the drive is limited by the 47K resistor. The charge time is about R2 x total gate capacitance, or 47K x 3nf = 141us, and during this slow transition the n and p transistors burn as ...
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If the current through a welder is hundreds of amps to melt metal, how does the welder circuitry cope
It's not the current per-se, but the heat at the tip - the arc - that heats the metal and forms the weld. The welding rod itself doesn't melt even with the several hundred amps through it. The ...
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If the current through a welder is hundreds of amps to melt metal, how does the welder circuitry cope
A simple spot welder might have an output like this. The wire on the secondary might be as big as a man's little finger.
simulate this circuit – Schematic created using CircuitLab
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"Output only" - IO Expander Question
It's explained in GPA7 & GPB7 Cannot Be Used as Inputs In MCP23017:
In the datasheet Revision D (June 2022), GPA7 & GPB7 are mentioned as outputs only for MCP23017. But, the register bits do ...
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DIY Wireless charger isn’t working
You will have a better chance at success with a reliable oscillator.
Start with this circuit.
https://www.electronicsforu.com/electronics-projects/wireless-led
9 V batteries are very weak, almost ...
- 15k
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Behavior of BJT collector current in saturation
How to explain the transistor behavior
I feel like your question is conceptual; that is why my answer is also conceptual. If I am wrong, use the other answers and let this one remain as an addition to ...
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Behavior of BJT collector current in saturation
Quote: "My question is: If we keep the base-emitter current high enough that transistor stays in saturation all the time, what will be the maximum current? Does the transistor limit the current ...
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How to read BJT output characteristic
Is it useful if there is no DC load line plotted?
The load line tells you the characteristic of the load, not of the BJT.
The characteristic of the BJT is useful because it tells you, for any choice ...
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Behavior of BJT collector current in saturation
If we keep the base-emitter current high enough that transistor stays in saturation all the time, what will be the maximum current? Does the transistor limit the current somehow in saturation or can ...
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Behavior of BJT collector current in saturation
What 'saturation' means is that the external circuit is controlling the current, not the beta*Ib of the transistor.
Any particular transistor might be able to conduct 10 A if it has low enough ...
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Behavior of BJT collector current in saturation
You are basically asking what will happen if you try to exceed the absolute maximum collector current.
First, hFE is not constant. It will decrease substantially at high collector current, so there's ...
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What makes some diode surge rated higher than others?
To add onto Neil's excellent answer, I'd just like to add some specifics:
Short time scales, on the order of ~µs, take place within the die;
~ms, heat is transitioning from die, through die attach (...
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Accepted
What makes some diode surge rated higher than others?
You can classify component heating into two extremes.
1 ) Long term
2 ) Pulse
1 ) Long term heating is limited by the thermal resistance from the junction to the leads and body of the device, and ...
- 162k
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Why doesn't the LED shut off?
For the NE5532, many reasons.
The input voltage range does not go very near the negative supply. So as your negative supply is the 0V ground, valid input range is upwards from 2 or 3 volts. So in any ...
- 137k
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Accepted
Why doesn't the LED shut off?
The opamp may have a large enough offset voltage so it requires the input voltage to be slightly negative to completely shutoff the LED. It will vary between opamps.
It can be avoided by intentionally ...
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What exactly happens when you connect two voltage sources in parallel? Why isn't it the same case when they are connected in series?
You're confusing reality and the way we model it. The circuit diagrams we use as models are imperfect. The connections between components have some resistance and voltage sources are usually more ...
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What exactly happens when you connect two voltage sources in parallel? Why isn't it the same case when they are connected in series?
What exactly happens when you connect two voltage sources in parallel?
Think of a 12 volt source connected to a 10 volt source. Can you see that is just the same as a 2 volt source connected to a 0 ...
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What exactly happens when you connect two voltage sources in parallel? Why isn't it the same case when they are connected in series?
The problem may be to think it pushes out electrons. It does not push out electrons. Maybe better to think in current, and the higher voltage source providing infinite amount of current and lower ...
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Resistance effects on LED when connected to battery
The 'forward voltage' given in an LED datasheet is a nominal value at a stated current (e.g., 20mA).
However, the LED current will vary widely with the applied voltage. Diodes (including LEDs) have an ...
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Accelerometer output mA/g; how to get to mV/g?
You add a resistor of appropriate value to ground.
Note that the scale factor is not well controlled- it's actually the current through an internal coil used to balance the accelerometer so it varies ...
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Accelerometer output mA/g; how to get to mV/g?
The brochure for this device Q-FlexQA-2000Accelerometer says:
The integral electronics develops an acceleration-proportional output current
providing both static and dynamic acceleration measurement. ...
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Accepted
Accelerometer output mA/g; how to get to mV/g?
To convert from voltage to current, you simply feed the current through a resistor to some reference voltage (e.g. GND) and measure the voltage across the resistor.
You have an output of \$1.2\space[\...
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Does this quesion have a solution?
It is solvable but you will have a lot of solutions possible. The total current flowing through the 2 resistor branches is fixed but the ratio of currents flowing through them is not constrained. For ...
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How to tell how much current can pass through a transformer
Here's a basic transformer specification (assuming there are no losses).
Primary voltage: 240 V 60 Hz
Secondary voltage: 24 V
Volt Amperes: 480 VA
Volt Amperes is the product of voltage and ...
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How to tell how much current can pass through a transformer
When you discover that you are looking at the wrong sort of transformer and, move-on to find the right sort for power AC applications, you would use the V.A rating of the device to calculate the ...
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How to tell how much current can pass through a transformer
Your first sentence has an error. A transformer does not change voltage down and necessarily boost up current.
And the currents you seek for the transformers are already in the first column.
And ...
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Solving for values in an NPN bipolar transistor circuit
It would help to know what simplified model of the circuit was used in finding those values. It turns out that the transistor was modeled as a current-controlled current source, with a fixed base-...
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Direction of current in a wire connecting two conducting loops placed concentrically in a time varying magnetic field which is into the plane of paper
The answer to this question depends upon assumptions that are not given in the question.
A time varying H (or B) field is always associated with an E field. It is assumed that the elements in this ...
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Accepted
Why are local AC transformers connected to ground?
Believe it or not, it's for safety. If it weren't grounded, it would "float" to quite high voltages relative to ground, mainly as the result of weather and other environmental effects. This ...
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Why does current flow through my body if I touch a hot wire?
This answer may shed some light on all this: Professor said no current flows to ground
Power lines are referenced to earth ground, and so are you, assuming you're not wearing insulated shoes or are ...
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Average Current vs Arithmetic Average
Average current.
If, by means of a rectifier, the direction of the alternating current is reversed every half period, so that a periodic current is obtained, but with alternations all in the same ...
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Could you drain a battery with only one terminal connection?
About the the lightning:
When the lightning strikes to the ground the current returns to it source. No contradiction here!
It has gone elsewhere a while when the cloud worked as static electricity ...
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Could you drain a battery with only one terminal connection?
In a PERFECT setup the battery will not discharge. However, non-perfect setups are very common. If you're having an issue with a battery draining over night disconnect BOTH terminals. I've learned ...
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