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How to distinguish different temperature wire insulations?

Wire insulations have different temperature ratings: 80°C 90°C 105°C 125°C 200°C These ratings can result in different current ratings for the same wire gauge. Are there ways to distinguish ...
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-1 votes
1 answer
17 views

Difference between the AD8561 and LM393 comparators

I am trying to build a capacitive touch sensor circuit on a breadboard such as the one on this website, http://www.learningaboutelectronics.com/Articles/Touch-sensor-circuit-with-voltage-comparator....
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1 answer
25 views

Sizing the DC/DC inductor for only momentary high currents

My DC/DC setup is going to power a GSM modem. The behavior of these modems is that they typically consume only a few tens of milliamps, but when transmitting they are drawing 2A for microseconds. On ...
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  • 143
0 votes
1 answer
33 views

LED driver resistors

I'm designing a circuit using an LED driver that is intended for RGB LEDs and uses a resistor to set the current for the constant current supply. On the LED datasheet, each color is tested at ...
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0 answers
26 views

Is this resistor manufactured by Piher?

I am attempting to determine if this resistor was made by Piher or not. The red color and glossy finish makes me think it was, however almost all the other Piher resistors I have seen have a different ...
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0 answers
34 views

Is this resistor metal film or carbon film?

I am trying to determine if this resistor is metal or carbon film? Traditionally most of the metal film resistors I've seen have been blue, while most of the carbon film I've seen have been light ...
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2 answers
43 views

Why mAh is constantly going higher?

I am kind of new in electricity, I bought a USB tester - KWS1902C. I can see my laptop voltage is constant 20 V (or around 20) to be more precise. Amperes are changing in sleep mode 0.002 when working ...
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-2 votes
0 answers
26 views

Excel data into waveform graph [closed]

I need a waveform of voltage (AC1V) and one of current (AC1A) against time. Is there a website that would be better ? I have been given only the data for the voltage and current.
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  • 1
-1 votes
1 answer
54 views

Am I overloading my circuit?

I'm using op-amps as schmitt trigger and with the resistors in the wheatstone bridge I am trying to control the flow of current in the load. When the load resistance is not connect between the outputs ...
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0 votes
1 answer
29 views

Use wirewound resistor as load

I want to use an array of ceramic wirewound resistor in series and parallel as the load of an 80W boost converter with the output of 400volts dc. Is it suitable to use 8 numbers of 10W resistors as ...
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  • 577
0 votes
0 answers
25 views

How to measure a DC motor's inertia

I want to measure the inertia of a DC motor. However, I have no idea how to measure or calculate this. I need the inertia to determine the numeric transfer function for voltage to angular velocity. ...
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2 answers
36 views

What makes difference in antenna gain pattern?

Let’s assume that we have a cavity backed antenna which has half-omni coverage, or call it unidirectional. We know that making it more directional will cause narrow 3-dB beamwidth, so above the ...
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39 views

Is there any advice for transferring digital signals at 8 MHz over loose wires?

My brother does steampunk stuff(?) He's thought of a contraption that requires eight digital signals (5V) to be transmitted at 8 MHz over a distance of 300 mm. To make it look sexy, he wants to use ...
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0 answers
43 views

Looking for an AC - DC power supply. Help on specs [closed]

I have been using my old auto stereo amplifier in my home and picked up a meanwell adjustable 0-48V DC. I would like to use a larger amplifier now and would like recommendations for the new supply. ...
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0 votes
1 answer
51 views

Inverter requirements for instantaneous water heater

I'm looking at installing a battery + inverter system for my apartment to keep things powered during frequent scheduled powered outages. I live in South Africa, where we have 2.5hrs "load ...
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  • 1,043
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0 answers
26 views

How To Keep USB Port Power On Samsung TV [closed]

I have a new 32in Samsung Smart TV and a led backlight strip that connects to the USB port on the TV. While the TV is On, the USB port is powered and we can use the light strip as we please. However,...
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  • 101
0 votes
0 answers
33 views

St802 alarm link? [closed]

I've moved into a new home, and the previous owner has died. No one seems to know the alarm code for the st802 hardwired alarm. I've pored through the manuals and to perform an engineer reset, it ...
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1 vote
0 answers
47 views

Why is the ACS712 VIOUT more stable with a current limiting resistor?

Below is my circuit for an ACS712 that is connected to a relay that joins to s capacitor bank: In the diagram I using two 5V power supply, one for relay module and one for (PIC,voltage reference,...
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  • 511
-3 votes
0 answers
48 views

Writing into flash memory [closed]

I am using STM32 HAL library for read and write flash. I have few questions: What will happen to data present in flash when we reset power? What will happen to data, if we flash new code with only ...
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  • 15
1 vote
1 answer
47 views

USB PD "multiplexing"?

I have a powerbank, which can provide power on its single typeC port. Provided power is PD-capable: voltage and current can be negotiated by the standards. The powerbank itself can only be charged up ...
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  • 385
0 votes
0 answers
32 views

Calculating watt usage from an input/output electronics spec for step-down transformer's minimum watt limit

I'm trying to calculate the minimum watt limit needed for a step-down transformer that convert 220 V to 120V from source (220V) to 125V smart plug then to an electronic appliance with the following ...
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  • 101
0 votes
1 answer
37 views

ESP32 DEVKITV1 - Can't generate waves in two cores

I'm using a ESP32 (DEVKITV1) to generate two waves in two different cores. Below is the code I'm using. ...
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1 vote
2 answers
70 views

Do holes in a semiconductor just move when there is a current going through the semiconductor?

If a current travels through a semiconductor holes travel to the "end" of a semiconductor, where they can recombine with incoming electrons. Does this also occur if there is no current ...
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-1 votes
1 answer
52 views

Looking for MOSFET [closed]

I am looking for 2/4 line, efficient MOSFET for switching on/off (not more then 1 per second) as per uP-ESP8266 have load <=120 mA at 3-12V but leak-current should be less then 10uA. I always used ...
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  • 103
0 votes
0 answers
40 views

ESP 01M LED circuit

I designed a small LED board using an ESP 01M. At first, the 5mm LED was working as I wanted. Sometimes the processor was reset, so I plugged a capacitor into the inputs and outputs of the AMS1117 and ...
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  • 21
0 votes
1 answer
51 views

Interfacing 2.85V logic modem with 3.3V microcontroller

I have Fibocom G510 modem. It has 2.85V logic level and datasheets says, that 3.3V is absolute maximum for logic pins. Maximum baud rate is 115200. Due to the limited space in the housing / on PCB I ...
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  • 5,764
0 votes
1 answer
54 views

Help identifying a fried power IC

I've got this fried IC on the mainboard of an HP ProBook that does not turn on, however some of the markings are gone: I assume it's a power IC or something related to the voltage regulators, since ...
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  • 219
0 votes
0 answers
19 views

Looking for an automatic switch to keep my two solar systems completely separate? [duplicate]

Here is a picture of my Queensland, Australian setup. My 4kW off-grid system needs to be completely separate from the house 3kW solar system, and also cannot touch the Energex meter box at all, ...
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0 votes
2 answers
36 views

How to check output voltages?

I'm attempting to repair a Dell P2210 PC monitor. I've traced the fault to a faulty diode on the power supply board. As part of the repair I would like to check the output voltages. The service manual ...
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  • 101
0 votes
1 answer
51 views

Python script to Verilog RTL [closed]

Can anyone give me an idea on how to implement an efficient Verilog HDL of the below Python code. I'm not asking for code or algorithm, just want someone to point to proper sources. I have posted only ...
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4 votes
2 answers
198 views

Is it possible to connect one voltage reference to multiple ADCs?

I am using REF3033 to provide a voltage reference to AD7685. Twenty ADC chips are cascaded in a daisy-chain manner, as was guided in the datasheet. Can I use one voltage reference chip for all the ...
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1 vote
1 answer
54 views

What is this connection for in this H-Bridge circuit?

I saw a different H-bridge circuit than the H-bridge circuits I’ve seen before. What could the connection to the MCU in the lower left of the circuit be for?
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  • 311
0 votes
1 answer
40 views

Does placing two optocoupler one below another in PCB design affect any signal?

I am working on a circuit where I am using multiple ultrasonic sensors which work on 24V, to read the sensor output through a microcontroller that accepts 5V. I am using optocoupler PC817 to maintain ...
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1 vote
1 answer
37 views

How does Kirchoff's current law work for sinusoidal voltage sources?

I was solving a steady state question with sinusoidal AC voltage source and the solution for the question used Kirchoff's current law to find the nodal voltage of a node. Now, I used to think that I ...
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  • 15
0 votes
1 answer
54 views

Do I need an isolation transformer?

I am building a 5V circuit where the maximum current draw I expect will be 5-5.5A, so have purchased a 5V 6A power supply IRM-30-5ST. In order to connect this power supply to the mains, I have ...
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  • 3
0 votes
0 answers
21 views

HP Proliant server power up issue with strange behavior [closed]

I have three HP Proliant G6 ML-370 server on my server farm. After a power failure and UPS battery full discharge all server went down. After city power was reestablished two server were OK and one ...
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-2 votes
1 answer
54 views

Why is this simple delayed LED circuit not working? [duplicate]

I cannot get this simple circuit to work. It is a delayed LED circuit. The circuit calls for a 10k resistor, 1000 uF non-polarized capacitor, LED, and a 9 volt battery. The only thing I have been able ...
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1 vote
0 answers
29 views

I2C read() lost 1 bit

I try to use I2C to read data from ADS1110, the address of ADS1110 is seven bits, which is 1001 000. Writing data can only change the configuration register, which ...
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0 votes
0 answers
23 views

Plug for Gree air conditioner display

To make an extension cable for the display of a Gree air conditioner, I need a plug and a terminal with the following data: 4 pin 2.5 mm pitch
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  • 1
2 votes
1 answer
56 views

Resonant frequency of power supply (audio amplifiers)

I simulated and built a Class AB amplifier recently, which is powered straight from a +-20V lab power supply. When testing, I noticed that there was a dip in the amplifier's frequency response at ...
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-2 votes
2 answers
84 views

Drivers in C++ produces bigger assembly [closed]

I'm trying to figure out whether C++ is a suitable language for use in device drivers, like peripherals on Cortex-M3/M4. I started writing some drivers for GPIO and I noticed that it produces bigger ...
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0 votes
2 answers
34 views

Implementation of a capacitive coupling circuit for power line communication (PLC)

Introduction: Hello everyone, I just wanted to see if there is anyone out there who is familiar with power line communication technology that can help me figure out what is wrong with my LTSpice ...
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1 vote
2 answers
49 views

Benefit of fully differential amplifier

I am trying to build an audio amplifier PCB with S/PDIF and single ended line level inputs and want to use the CS42528 CODEC (datasheet). My questions are regarding the input and output stages of this ...
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-1 votes
0 answers
37 views

How to input proper components in bjt voltage divider given only the gain? [closed]

I'm currently making a bjt voltage divider bias circuit and don't know how to input the proper components such as values for capacitor, vcc and resistance and the gain is exactly 57.Because after this ...
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5 votes
3 answers
456 views

Will this mains disconnect circuit work?

The purpose of this circuit is to disconnect a home wiring from the grid when there is a power failure without having the power contactor coil working 24/7. Where I live, when the power is restored ...
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  • 51
-1 votes
0 answers
22 views

How can I perform STDP (Spike Time Dependent Plasticity) using Keithley 2450? [closed]

In order to perform Spike Time Dependent Plasticity (STDP) characteristics of the perovskite-based memristor devices, I want to learn how can I program my Keithley 2450 to perform STDP of my devices. ...
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  • 1
1 vote
1 answer
44 views

D flip-flop frequency divider

I'm using a transmission gate base DFF to build a simple frequency divider. It worked, but I'm getting some weird waveform at some intermediate nodes and the power consumption is high too (11 μW). ...
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  • 71
2 votes
1 answer
55 views

GPIO pins not changing state - unsure how to debug

I am using an STM32F072CB. Some of the GPIO pins are connected to a multiplexer for controlling the channel, and others are connected to some MOSFETs. The pins are configured as regular no push/no ...
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-2 votes
1 answer
49 views

Microelectronic Circuits (Sedra Smith) book does not cover the Sallen-Key filter topology? [closed]

I've started an electronic circuits course which comprises active filter design. One of the topologies studied for Butterworth filter realization is the Sallen-key. I am using Microelectronic Circuits ...
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0 votes
0 answers
11 views

Why is my asynchronous register losing its value in Logisim?

I am designing a 4-bit CPU for my own fun purposes, but I have an issue with automatic instructions on my asynchronous register. The Problem If I execute the load instructions manually (i.e. switching ...
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