Questions tagged [voltage-detector]
The voltage-detector tag has no usage guidance.
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Non contact AC voltage detector circuit current calculation
This seems to be a common circuit for a non-contact AC voltage detector:
Non-Contact AC Line Detector using BC547
The probe generates a small amount of current when it is near an AC line due to ...
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Chip identification, SOP-4, "HPTD"
Anyone know what this chip is? The dimensions are approx 4mm by 2.5mm. Also I believe one of the pins is connected to Vout of a voltage regulator. Could it be a voltage detector?
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Detecting 220vac with optocoupler and microcontroller on lines that have capacitive coupling voltages
I'm a hobbyist, trying to instrument my heating system so that I can control a three position valve. I have an ESP8266 integrated with a DRV8825 stepper motor controller, and a no-name Chinese 220vac ...
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Detecting 16 V AC with a GPIO
My project involves detecting a ringing doorbell. The doorbell circuit is 16 V AC and I want a low-voltage binary signal from it. The obvious way to me is to transform that electrical signal until ...
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Window comparator to drive LED
I’m struggling to build a window comparator circuit where the output is high when the voltage is in range. I do not have access to any kind of inverter. I have tried using an inverting op-amp, but ...
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How to detect voltage peaks above a set threshold?
I have a power source that will generate voltage peaks for a very short amount of time (around 20 - 100 Microseconds long). I am trying to develop an electrical circuit that will capture the peak ...
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Simulating HCPL-3700 using LTSpice
I am trying to simulate HCPL-3700 using the LTSpice model provided by Broadcom.
Following the application note 1004 example 1, I am able to successfully calculate the Rx value and simulate the model ...
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BLDC back-EMF zero-crossing detection using comparators: resistor confusion
I am building a sensorless BLDC driver development board using an RP2040 chip and I plan on detecting the back-EMF using comparators. After reading quite a bit about the BLDC phases and methods to ...
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How does this transistor-based voltage detector circuit work?
I was looking to see if there is a low voltage detection circuit that could be made without ICs. I found this circuit but with the given values and configuration I don't understand how it could work. ...
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Detection of mechanical relay sticking
I'm exploring new methods to find if relay contacts have been stuck together without using auxiliary contacts of the relay. while searching I find out this block circuit:
at this Toshiba page
as far ...
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How to detect a sine wave signal to trigger a logic gate? [closed]
I need a way to detect a signal input and then output it as a logic high. The signal input has a 40 kHz frequency and it's a sine-shaped signal. The amplitude is not sure, could be from 12 V to 1 V.
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Would this isolated AC peak voltage detection circuit work?
I have adapted the circuit from Michael's circuit in Efficient method for isolated detection of AC voltage without a stepdown transformer to detect on either side of the positive half-cycle peaks, ...
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Why I am seeing small voltage in the voltage display from detector?
I am using this detector to detect the brightness of an LED (powered and controlled by controller). When I use this multimeter to measure the detector output, I see the range of detector from 0-12.13V....
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Cheapest HV AC detector
I need to detect AC voltage with MCU for ensure relay health condition, the cheapest and smallest solution are most welcome.
I have no hard time restrictions or noise canceling\debounce requirements (...
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Voltage detector with ajustable time delay in a THT package or build own simple small time delay?
For my project I need to delay the enable signal from an esp32 for a 50MHz clock by a bit - The examples I use on how to do that only ever use a BD523 with non-inverted output. For testing I want to ...
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