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36 views

how to select LED protection device?

I have this simple LED configuration: Voltage source is 24VDC so with the 1k resistor and three 2V LED, current is around 20mA. I want to put a PLED device across each LED. how do I select correct ...
0
votes
1answer
61 views

Is there as way to verify a spectrum analyzer setup?

I just finished setting up my spectrum analyzer and I would like to ensure that everything is as accurate as possible. I was thinking of getting some kind of RF transmitter that transmits at a ...
1
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1answer
39 views

SMPS Simulation Help

Finally bit the bullet and considered getting help with a simulation I'm looking to get right. Just a heads up, I have limited experience with SMPS simulation in both LTSpice and Multisim. The circuit ...
0
votes
3answers
162 views

How can I remove noise in my preamplifier circuit? [closed]

I need a low noise microphone preamplifier for my Arduino. I used a battery and standard wire but I had noise in my circuit. I need gain 20-20kHz. Can you help me with the schematic?
0
votes
1answer
40 views

Logging and retrieving large bursts of sensor data from an Arduino

I was wondering, if I put an Arduino with a few sensors on let's say a water rocket to track acceleration and height and what not, how would I save this data? I'm assuming that I want to have a high ...
0
votes
1answer
49 views

About to start a new project I have some questions before I start

So I am going to start to build a table that will have two different stands of lights, which are linked below. I was planning on using an 18 volt Milwaukee battery, but after getting the lights, I ...
-1
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0answers
65 views

Mains voltage measurement

Consider the schematics on the figure. The aim is to measure (sample for e.g.) mains 220V voltage. MAINS_1 is phase, ground is connected to neutral. The most obvious idea is to use a transformer, but ...
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2answers
50 views

What happens if an inverter neutral is bonded to earth

My question is similar with this question: https://physics.stackexchange.com/questions/299199/will-a-battery-connected-to-the-earth-eventually-deplete#:~:text=First%20off%2C%20every%20battery%20will,...
1
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2answers
67 views

How to solve this non ideal inverter opamp?

it is asked to make a non ideal inverter opamp that has an input of 2mV or and get an output of -100mV, so I think the next circuit should suffice. simulate this circuit – Schematic created ...
0
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2answers
66 views

What sort of oscillator topology is used in WiFi/BT transmitters?

Thinking of cheap(er) consumer wireless products. Modulator aside, how is the RF carrier signal generated? Do they use really small capacitances/inductances on a chip die to make an RLC (say, Colpitts-...
1
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4answers
132 views

How does this RC pulse generator circuit work?

In this video from Ben Eater, he uses an RC circuit to create a push-button "write-pulse" generator for his EEPROM (discussed around the 14 minute mark) that ensures the write pulse fits ...
0
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0answers
40 views

Identifying and finding a replacement audio signal transformer 50 ohm / 0.5 ohm

I am trying to identify and find a replacement for the attached transformer. The green/white leads with the red center tap have a 50 ohm resistance. The side without the center tap has a 0.5 ohm ...
0
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0answers
14 views

Error while simulating the speed control of a brushed DC motor using a 555 timer and a high boost convertor using Multisim simulator

Reference paper: https://ieeexplore.ieee.org/document/6183251 I'm trying to simulate the speed control for a brushed DC motor using a 555 timer (astable multivibrator) and a high boost convertor using ...
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0answers
15 views

VPC0820 Li-Ion Capacitor how to understand the 97% Self Discharge (V) parameter

Does anyone know what does the self-discharge parameter mean? I know what self-discharge is, but what does over 97% mean?
0
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0answers
28 views

Can I get power from my Thermostat's AC relay wires?

I have a 2-wire thermostat that activates my baseboard heater when the 2 wires are shorted. I did an experiment closing those two wires with a relay and got that working well with an ESP32 as the ...
-1
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0answers
13 views

AC 3 phase servomotor current mode

How do i mathematically model a 3 phase ac servomotor's current control mode? someone please help me. The model of the the servomotor is BSM132C 5200AA Thanks
5
votes
3answers
881 views

5V to 400V boost converter problem

I am trying to make a boost converter that step up 5V to 400V. I am doing it for a geiger counter. I know that it's complicated, but it should be possible. Anyway, here is my schematic: My problem is ...
0
votes
1answer
29 views

Gate noise on KA3525

I am designing a 1kHz inverter in a push-pull configuration with KA3525 and IRF540N MOSFETs. Input - 12V Output - 110Vac - square wave filtered to sine wave Power - 15W at 1000Hz When I fire it up ...
0
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0answers
46 views

What is the bible for electric motor design? [closed]

For engine design, there is The Fundamentals of Combustion Engines by Heywood. This is generally regarded as the bible for combustion engine design, and deeply covers almost all aspects of motor ...
0
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0answers
21 views

Using STM32F4 Discovery I/O PINS attached to another device on the board [duplicate]

I am trying to communicate with a device over SPI using an STM32F429 Discovery kit. I would like to use the SPI5 but according to UM1670, table 7 and STM32F429xx Datasheet, table 12, page 76, there is ...
-2
votes
1answer
77 views

AC circuit voltages and currents

I have this circuit: Have I done everything correctly? I cannot find my mistake. Help appreciated.
0
votes
2answers
71 views

Keyboard USB transform

I want to press a key on my keyboard, for example "a" and a device should take the scan code of the button I pressed and transform it to something else: e.g. "b" or the scan code ...
2
votes
0answers
40 views

200 Input Smart Multimeter Project

First off, thanks for taking the time to read this and help out. Here's a quick overview of what I am trying to design. I have a break out box that has 200 female probe inputs. Each input is numbered, ...
0
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3answers
77 views

Trapezoidal wave RMS value

I am calculating RMS value of trapezoidal wave. I found its formula like below: and at last the RMS value formula: u = 30degree or pi/6 --> especially pi/6 A = 12 When I calculate RMS value by ...
0
votes
0answers
23 views

Can I use 2 H-Bridge for drive a motor?

I've a 12V 80A motor, for drive this i'll use a H-bridge with mosfet, in order to divide the current per H bridge we can drive a motor with 2 H-bridge? I'll use mosfet, we cant put mosfet in parallel
0
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4answers
63 views

TO-247 case maximum current

I've this TO-247 MOSFET http://www.datasheet.es/PDF/203551/2SK3271-01-pdf.html how much current will support this case? I've to control a 12V 80A DC Motor
2
votes
2answers
115 views

Would a faraday cage still work if it was part of a circuit?

Faraday cages protect against EM radiation and charges. As far as I understand, this effect happens through the induction of an electric field, which produces a current inside of it, which then ...
1
vote
1answer
54 views

Voltage to GPIO pins

Interested in Embedded Systems, I'm coming from Computer Science background. There is a thing that I can't get my head around for awhile about pins of GPIO. Let's say that we have a port which is ...
0
votes
3answers
93 views

Getting glitches on GPIO using a MOSFET as a logic level converter

I need to connect an Event Detection pin (pin of the NXP NTAG 5 component) to a GPIO of the NXP i.XM6 processor. The problem is that the NTAG 5 pin has a logic level of 5V and the GPIO has a logic ...
1
vote
1answer
57 views

What is the output logic levels of this STM32?

I am struggling getting my head around the input and output logic levels, mostly the output levels of this STM32 (STM32F446xC/E). This table shows the output logic levels as dependent on if it is a ...
0
votes
2answers
59 views

Change LED blinking frequency depending on voltage

I'd like to make an LED blink with a varying frequency that depends on a voltage. I know about the 555's control pin, but I'd like the blinking to vary continuously, instead of switching between just ...
1
vote
1answer
41 views

Pulling different voltages directly from AA alkaline cells wired in series

I need to power a miniature LED light show that will draw a few hundred mA, or possibly more, and requires less than 5 Vin, and a microcontroller board that wants 7-21 Vin. I was thinking the easiest ...
0
votes
0answers
15 views

Mixed Sensitivity Problem

I have plant, $$P(s) = \frac{1-s/5}{(s^2 + s/4 +1/4)}$$ I am taking a mixed sensitivity approach for that I have chosen \$V\$,\$W_1\$ and \$W_2\$ as follows: For bandwidth, \$\omega\$ =1 so I chose M ...
0
votes
1answer
54 views

Sizing Through-hole Vias for Power Traces

I am trying to understand what size vias I should use for my 5V power traces. The trace typical runs at 0.5-3 amps and is 2mm and about 150mm in length. The width is huge, but I do have the extra ...
3
votes
6answers
569 views

Why is my low dropout voltage regulator Diodes AP7370 burning up?

I'm building a LED driver using Diodes AL8871Q IC to power a XHP70 LED powered from a 4 series protected Lithium battery pack, integrated on the board it has an Attiny85. I plan to use the Attiny85 to ...
0
votes
1answer
22 views

Thermal voltage of Ge diode

What is the thermal voltage of a Ge diode?I know for a silicon diode is about 26mV at room temperature. I have this circuit: simulate this circuit – Schematic created using CircuitLab and a set ...
0
votes
1answer
36 views

What determines the power requirements of a IC

This is more of an acquiring more knowledge question. I have used a few ICs, such as the 741 op-amp, AND, OR, NAND gates, etc. I have also used a few micro-controllers like the atmega32, atmega328, ...
0
votes
0answers
49 views

Can I wire a wall switch to my circuit?

simulate this circuit – Schematic created using CircuitLab Can a wall switch be wired to a DC circuit like these two circuits??
0
votes
0answers
18 views

Control RF controlled LED panels with a Raspberry Pi 4

I'm trying to "smartify" my LED panels by controlling them without the actual remotes. My goal is to make it possible to control the lamps from an http endpoint. I have an Raspberry Pi 4 as ...
-2
votes
1answer
75 views

How to tell correctly if a circuit is pull-high type or pull-low type?

I have been giving this assignment working with Arduino that would light up a 7-segment component, when a push button is pressed. Is there an intuitive way of looking at the circuit and recognize ...
0
votes
0answers
18 views

Issue using TCC3 of microchip SAMD21J in variant file

I am writing variant files for SAMD21J/G/E. I am unable to use TCC3 of SAMD21J/G/E in Variant.cpp for arduino IDE. If it is used Arduino IDE shows error TCC3 undeclared variable whereas, all other ...
1
vote
0answers
39 views

opamp single supply output AC (audio) voltage limit

I build non-inverting op amp with single supply voltage cca 9V. The basic scheme is shown in the figure below: How to limit output AC signal if the base DC voltage is at half the supply voltage 4.5 V ...
-1
votes
1answer
49 views

400Mhz frequence HackRF One

All, Sorry but I am new to this topic and have no experience with SDR myself.First, I briefly give the hardware that I am using: HackRF One Following antenna: https://zsecurity.org/product/atheros-...
2
votes
0answers
73 views

Image recognition for PCB - is this available?

I have a populated PCB, and I want to draw a circuit diagram of it. For printed documents, you have OCR which can recognize text in an image. Is something similar available for PCBs? i.e. I provide ...
0
votes
0answers
13 views

What is the right BMS and S/P configoration

the cells are 3.2 volt at 280ah buy 32 cells what is the best 12/24/28v and the best BMS for setup I have all ready purchaced cells and am waiting on delivery to install in my rv
0
votes
1answer
56 views

Shift-register seems to read wrong input data

Here the schematic of a small board with a 74HC595 shift-register: Here the detail of each output. They are connected to QB..QE. Nothing is connected to the collectors of BJTs and the board contains ...
0
votes
2answers
56 views

What's TL431 Output voltage

I am using PSIM to simulate the TL431, and I have some questions. This is my PSIM circuit: When Vref is less than 2.5V, the TL431 doesn't conduct, it looks like an open circuit so Vo is almost 5.1V. ...
0
votes
3answers
64 views

High gate pin current leakage on a p channel mosfet

I have added a P-MOSFET before my main circuit, between the v+ of the battery, and the Vcc main power line of the circuit, so that the battery stays disconnected and doesn't drain until I am ready to ...
0
votes
1answer
36 views

I2C Shifter being used to protect against short to much higher supply rail

For a device I'm retrofitting, there is a risk that some I2C datalines could be shorted to a supply rail that can be between 12-44V, or ground To the best of my understanding this bodge circuit per ...
-2
votes
0answers
32 views

I cant contact about OP amp Analog VLSI [closed]

I hope to know the formula how to get Max output voltage and min output voltage, output max souring current, output max sinking current. also Gain ... how to judge them in this circuit...? Also, I ...

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