New answers tagged current-measurement
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Why does a brushed DC motor current draw differ with direction of rotation?
The motor timing has been advanced by turning the end bell counter clockwise. When run in the normal direction (positive wire connected to the side with the plus symbol) you will get more revs. When ...
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PAC1921 power monitor issue
When I'm trying to get Vpower, I always get zero and I can't understand how to get current flowing through resistor, i.e how much current STM32 MCU consumes.
First of all, you should also explain the ...
- 30.5k
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CR2477 battery peak pulse
With the following design parameters:
Peak-Current 20mA
Peak-Duration 5s/60min
Voltage nom. 3V
Voltage min. 2.5V
IBatteryMax 2.5mA
I would come up with the following circuit:
simulate this circuit &...
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Analogue Read in ESP8266 WEMOS D1 MINI is fluctuating
Take under interrupt (every 1 ms for 50 Hz mains) 21 samples.
Calculate the "mean" measure.
When done, you can calculate the RMS value of the current.
As in this file for ATmega328N under ...
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Analogue Read in ESP8266 WEMOS D1 MINI is fluctuating
You are taking one sample per 1 second.
Taking the sample could be from any position in the waveform of current, so taking one sample per 1 second means nothing about the waveform of the current, not ...
- 138k
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Measuring accurate voltage across a shunt resistor for high frequency AC current sensing
You didn’t state your accuracy requirements.
A current transformer may be an option which handles isolation and amplification (to an extent)but won’t be super accurate.
Single ended measurement is ok ...
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Measuring accurate voltage across a shunt resistor for high frequency AC current sensing
It all depends on your transformer. Note that the opamp tolerable voltage range and voltage supplies must be larger than the largest voltage swing you expect at the output. This circuit is configured ...
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Which op-amp should I use to measure voltage across a current sense resistor?
Analog Devices has precision op-amps with ‘over the rail’ capability that can be used to sense current on the high side. This is much more convenient as you don’t have to break into the load's ground ...
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Which op-amp should I use to measure voltage across a current sense resistor?
I came across a similar question.
That's what I realized:
The operational amplifier can be with a different type of power supply: unipolar (for example: +12V and ground) or bipolar (for example: +5V ...
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Comparator as a current detector with shunt resistor v2
To detect two different voltages, you need two comparators. You also will need two separate reference voltages, one for each comparison.
The LM324 is an opamp, not a comparator. If you want to ...
- 18.3k
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Comparator as a current detector with shunt resistor v2
You can simply add a second op-amp with the appropriate negative 1V reference voltage and 'or' the two outputs with a couple diodes and resistor to -V or GND.
simulate this circuit – Schematic ...
- 385k
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