Questions tagged [current-sensing]
The current-sensing tag has no usage guidance.
174
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Current sensing nA to mA
I need to sense the current of a target MCU through various periods of its on/sleep/off state and then need to send this data back to another interface MCU to read out the value. They will be both on ...
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Is it feasible to measure voltage drop across 0-ohm jumper resistors to determine excessive current draw?
We design very low-power devices which in standby mode use about 8 µA of current. They are powered by 3 V lithium primary cells and are designed to last for many years.
Every now and then we see a ...
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How is this a current mirror?
This article is talking about floating an IC's GND to use it at a common mode voltage higher than it is rated for. It then says it level shifts the IC's current output to ground by using the Q1-Q2 ...
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What is negative current?
I understand that voltage is relative to ground, so that can be negative.
However, I'm currently looking at current-sensors (ACS712 current sensor) and in the performance characteristics table, it ...
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Can a floating capacitor terminal be used to collect electrons?
I want to collect charge from an electron beam source. For that, I'm proposing to put a floating capacitor with its bottom terminal floating and directly exposed to the electron beam gun. The top ...
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1
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Is it wise to determine heating element temperature from resistivity?
Context
I'm making an electric furnace for melting metal, and aiming to make my own controller.
Everyone seems to just use thermocouples and a control loop, I thought perhaps I could just measure the ...
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2
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The benefit to make or use a surface mount 4-terminal current sensing resistor
I find some precision SMD resistors are 4-terminal, like vishay's CSM3637P. It's constructed as below:
It seems it only make a slot on each pad, then get two extra pad to do the voltage measurement.
...
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Measuring average current consumption in hardware
I'm working on a very low power budget, battery powered project. This project is allowed to draw 15uA (average) at 3v. The microcontroller we're using draws 4-10mA when active, and 2-3uA when asleep....
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Wide range current sensing at +5kVDC
I am working on a control and interface board for high voltage supplies, which requires some current measurement to be implemented. The general terms of the question are similar to this one. The ...
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3
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Op amp with transistor in feedback
I am currently looking for a high side current sense IC. I have noticed that most of them that are without galvanic separation, are using an op amp with bjt transistor like in bellow schematics:
The ...
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Charge indicator with comparator - very sensitive to noise
I need an indicator when the current from my charger is larger than 100mA. I tried the below circuit but this seems very sensitivity to noise. Probably I am getting some ripple in the mV range from ...
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Noise problems in current sensing
I have the following circuit:
simulate this circuit – Schematic created using CircuitLab
I am using a motor from an electric bike, as a generator and I am rotating it using a drill, to test ...
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2
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Can a non-invasive AC current sensor measure DC current? [closed]
Can a non-invasive AC current sensor measure DC current? What is the theory behind it?
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Detecting switch closure
Any techniques/circuits/sensors that can determine the open/closed state of a set of contacts, independently of whatever power or signals are being switched by the contacts?
Obviously easy if there's ...
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ESP32 using acs712 give wrong values
I'm trying to measure current with acs712 30A current sensor connecting to NodeMCU-32S but I'm getting wrong and unstable values. For zero current the ADC pin should read value of 2048 (esp has 12 bit ...
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