Questions tagged [current-sensing]
The current-sensing tag has no usage guidance.
180 questions
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Dedicated current sense amplifier vs simp,e difference amplifier
I need to implement low-side current sensing for a H-bridge motor driver. While there are dedicated current sense amplifiers such as TI’s INA180, can I use a simple difference amplifier for this with ...
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Why most non-invasive current sensors have a minijack at the other end?
If I search on google for non-invasive current sensor and click on the images tab, in most cases, I see a minijack at the other side of the wire.
What is the reason for this? Is this minijack supposed ...
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INA219 current sensor not working properly with DC motor
I use INA219 module to read DC motor current for control propose.
I connect INA219 in series with motor as shown in schematic.
simulate this circuit – Schematic created using CircuitLab
The ...
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Load sensing relay/power switch/adapter which switches on when it detects some load on its input
Complete newbie here. I'm not using the right terms, so my apologies in advance.
The problem is simple. I want my powered computer speakers (2.1) to turn off when the computer is turned off. I have ...
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Adjustable CC/CV supply with voltage and current limiting having no output voltage at low voltage levels?
Im trying to create a power supply with an addjustable output between 0-12V or 0-3A (CV and CC adjustable). To make sure that the components don’t get damaged I'm trying to implement a protection for ...
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How to share a current sense pin on a single GPIO
The BTS7040 is a 2 channel High Side Switch with diagnostic feature, im planning on using 2 of the IC and i dont have extra GPIOs to spare.
The way you read a fault from the BTS7040 is to select a ...
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Detect power outage and disconnect heavy loads from the UPS [closed]
I am looking for a simple system to detect power outage and disconnect heavy loads from the UPS backup to maximize the longevity of the power backup.
The UPS works on a 24-V battery.
The UPS switch ...
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How to sense current AC of a sinusoide -100mA to 100mA with 70kHz
Any suggestions about a chip or PCB component that could work?
I tried to use the the current sense transformer PA1005.050NLT https://www.digikey.com/product-detail/en/pulse-electronics-power/PA1005....
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How to average output of current sensor to get smooth output?
I am using INA138 current sensor with 100Hz, PWM duty 5%, 8-bit resolution signal load is a resistor,
I getting zero readings while actual current readings also appear,
edited -
zero current sense ...
- 194
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Designing high bandwidth current sensors for inductor current sensing
I am designing a high-frequency current sensor, suitable for sensing +/- 20 Amps at frequencies of 200kHz. This is being used in average current mode control application in an isolated forward ...
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Microamp-milliamp Measuring Circuit: will my circuit work? Feedback/Advice
I'm developing a device which must be able to measure milliamps and microamps on one of its lines (down to 1 microamp, but also clearly seeing if it's less than 1uA). It's going to be DC of different ...
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886
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Converting a 4-20mA 24V signal to 0-5V?
How do I convert a 4-20mA 24V signal to a 0-5V signal, suitable for A-D conversion with a 5V microprocessor? Can this be done while isolating the 24V from the 5V output?
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Current sense op-amp with integrated shunt vs expensive resistor
To simplify my question lets assume:
I need to convert +/-7.07A RMS AC current into +/-707mV RMS voltage with high acurracy (0.1% or better).
It may be also higher voltage, up to +/-2.5Vpk.
For now ...
- 6,064
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Detect Battery Insertion in USB Charging Circuit
I'm using an MCP73831T as the charger IC, I've figured out how to detect the charging/charged, this was easy, however, I would like to know when the battery is actually plugged in, I know when the usb ...
- 153
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Current Sense Amplifier Potentials
I'm trying to implement a current sense amplifier in my application, but I have a question about setting it up with regards to current flow.
Basically, in this case, you put a very small shunt ...
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Current Sensing on positive and negative voltage rails
I'm working on a design that uses two separate buck regulators to generate a positive and negative voltage, and I'm trying to implement current limiting with a current sensor. However, I am running ...
- 22k
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I am looking for a 40 input OR gate which minimize PCB space
I am using 40x ICs INA301 to measure overcurrent in 40 interfaces
Finally I want to have 1 single "output" to signal if there is an overcurrent in ANY of the 40 interfaces
I don't want to utilize any ...
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248
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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 ...
CommunityBot
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Method for sensing fault currents with microcontroller
How do I choose a proper approach for detecting ground fault currents (20 mA through 30A, 60Hz)? Let's say I have a zero sequence CT and calculate a burden resistor. I have a 12-bit ADC in the micro. ...
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725
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Current sensing relay with delay on break for dust collection system
I am in the process of planning our a new workshop in a single car garage. I have a large 20A Dust Collector that needs to be on its own circuit or else it will trip. I also have a ceiling mounted ...
- 7,259
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3
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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 ...
CommunityBot
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High voltage and cheap differential amplifier
Can I use a LM324N (very common) op-amp to act as a high-side differential current sense op amp at high voltage?
The Differential Amplifier
The differential input voltage rating is 32v, but my load ...
- 81.6k
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Current monitor output doesn't respond to load changes
When I physically build this circuit the output voltage doesn't response to load variation.
The voltage across the sense resistor is definitely increasing when decrease the load resistance, the ...
CommunityBot
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Measuring high currents with toroids
I got a PT27312 current sensor (datasheet), I wonder if I can use it to measure currents up to 100A AC/DC.
I couldn't find any specifications in respect of the current measurement range.
I only know ...
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511
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Working Voltage for Basic/Reinforced Isolation (ACS712)
I'm planing to use current sense chip ACS712.
I don't understand some values in its datasheet, page 2 (Isolation Characteristics).
I understand "Dielectric Strength Test Voltage - 2100VAC" - that ...
- 100k
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429
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"ground disturbance" in current sensing with shunt resistor
There are lots of questions about "traditional" low-side current sensing using a shunt resistor.
Most discussions and papers mention the drawback of "ground disturbance" introduced by the measurement ...
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XADC Current Sensing Reference Design
Please refer to this reference design for AC701 (snippet below).
The schematics, specifically the current sensing sections in pages 34-36, show this:
I want to understand why, for the REF output of ...
- 473k
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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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How to connect multiple sensors to single PLC input?
Hello. I have a scenario where I have multiple PNP "error signal" from several sensors (let's assume 3 for now). If the sensor output is HIGH, then there is error. If the sensor output is LOW, then ...
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Current transducer - understanding of turns ratio connection
I'm using a LEM LAH 25-NP current sensor and I don't understand the recommended PCB connections in the table from the datasheet. I understand the first one, but what is with the second and third? What ...
- 473k
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Current sensing using XADC
AC701 Schematics
Refer page 40 of the schematics. Here for Vccint- the regulator is switching at 250 kHz.
page 34 has the sensing signal conditioning for that the inst. amp used is INA333 which ...
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Current Sensing Amplifier Circuit explained
I've been trying to understand why each every comment is in the circuit shown. I understand that the amp is taking the voltage drop across the Rsense and amplifying it such that the current across it ...
- 3,796
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INA168 vs INA169 High-side current sensing
I have read the datasheets of the INA168 and the INA169 and can't see any difference, other than internal resistors value and quiscent current (25uA for INA168, 60uA for INA169). Those two were even ...
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Sensing Voltage and Current of an Adjustable Voltage Source
I am currently working on an Adjustable Voltage Source, the Voltage Source is built by a voltage regulator with an OpAmp with and a Darlington transistor for current amplifying as the following ...
- 148k
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2000A current sensing using STM32
Is there any chance to read 2000A using STM32? I searched the Internet for low-value shunt resistor but nothing found. maybe some kind of current transformer could do the job!!
any help will be ...
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Buck converter design using MCP1630V
I have already designed a buck converter with the following specifications using an MCP19035:
Vin=14V,
Vout=1.8V,
Fc=63kHz(Crossover frequency),
Vref=0.6V,
Iout=10A
step load High IOH=7.5A
step ...
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Using a switching DC-DC converter in high dynamic range current/voltage sensing
I'm thinking of making a power meter circuit which will have a high-side current-sensing amp (LTC6102), a resistive voltage divider for sensing the voltage, a dual op-amp (OPA2365) as a buffer for the ...
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H-Bridge Low Side Sense Resistor - Position of Resistor and Bulk Capacitance
My question regards the considerations required in determining the location of a current sense resistor on the low-side of an H-Bridge. I've presented two scenarios.
Details: The H-Bridge load is a ...
- 16.8k
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Placement of sense resistor on DC-DC converter
For my design I am using DC-DC converters LTM4620 and LTM4644, which integrate the MOSFETs and the inductor in the chip.
For measuring the output current, I will add a sense resistor in each output ...
CommunityBot
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FOC sensor vs sensorless
I am trying to understand the hardware difference between the sensored and sensorless FOC 3-phase Induction Motor Drive circuit.
So far what I understand is that FOC require following sensors:
1. ...
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High side current sensing for negative high voltage
I need to monitor the current for a negative high voltage supply.
I implemented the following circuit in a simulation program:
https://www.maximintegrated.com/en/app-notes/index.mvp/id/1867
But ...
- 16.8k
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SMPS Current Sense Resistor Selection
I am looking into using an SPV1040 boost converter to charge a battery from a solar cell. The chip includes inputs for a current sense resistor, which are described in one of ST's applications notes ...
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Shunt resistors and PCB layout
I have several questions about the current sensing through a resistance.
The resistances are 2-SMD package and I will use the 4-wire kelvin method for the layout.(see image) Specifically, there are ...
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High-side current sensing diagram
I have a load that can be connected or disconnected from a +5V source (let's assume there is a switch). My target is to trigger an output to high-level voltage if the load is connected, and trigger it ...
CommunityBot
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Current sensing for side channel analysis
I'm trying to design a power supply with a built in current sensor for a digital system. The purpose is for side channel analysis. In current sensing, I would like to detect both the AC and DC current....
- 42.4k
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Over-current sense
I am using a circuit shown below.
it is designed to sense 1.5 A whenever the load takes current >= 1.5 A. Rsen senses the related voltage and activates the transistor.
Here I use a Rsen = 0.46 R(0.7V/...
- 26k
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Four-terminal resistor pinout?
Anyone can tell me (or preferably, point me to a source that explicitly shows) the pinout of the 4-pin current-sense resistors?
I'm seeing the datasheets for three different models (including Rideon'...
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Current sensing on negative 1.1kV DC rail
I searching for a way to do high side current sensing on a -1100V DC rail.
My HV is generated from the hamamatsu C9619 High voltage power supply module and it powers the hamamatsu R647P ...
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Overcurrent Sensing
I am designing an overcurrent protection circuit. I am sensing current with a LEM sensor across a sensing resistor of 16.5 ohm. The voltage drop for maximum current is 2 V. In the next stage I am ...
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