All Questions

0
votes
0answers
7 views

Tool for designing electrodes for PCB Mill Machine

I need to draw really simple layout, where i have only 2 electrodes and traces for them. Electrodes are 2x2 cm squares and i need traces to be thin like 0.15mm. I will need to create gcode from this ...
1
vote
1answer
24 views

resolution bandwidth

I have the following trivial question: I have acquired a noise spectrum with a resolution bandwidth of 124 Hz. I would like to convert it to V/sqrt (Hz). Shall I simply multiply or divide the signal ...
0
votes
0answers
16 views

“Solder PCB High Voltage connection” or “Flying Lead HV connection” reed relay model for high voltage PCB design?

I'm searching for the HV reed relay solution for channels multiplexing board design: V < 6KV, I < 10mA. 8 relays that connect 8 input pins to V or GND (given for an external supply device). ...
0
votes
2answers
50 views

What is the triangle components in this diagram?

I am reading through datasheet of a voltage translator for I2C (FXMA2102) and I cannot understand the triangle components in the block diagram: Are they diodes to make current flow in one direction? ...
1
vote
3answers
30 views

Is this way of sizing the series resistor for Zener regulator correct?

This is a completely made up imaginary question to ask the question easier. Let's say I have a 0.1W 5V Zener diode. And I want to use this to regulate from 9V to a 10k load. I draw this as in the ...
0
votes
1answer
29 views

Long Distance High Speed Wireless Data Transfer

What kind of device can I use to transmit data at a rate of 1MB/min up to a distance of 100 miles? If that's not possible, what's the farthest distance to which I can transmit the data.
0
votes
0answers
42 views

Need help getting started on my first project - Flexible PCB circuit routing

I am new to electrical engineering so I am trying to explain my project in simple words - please excuse wrong terms, etc. :) The software part is less an issue for me because I know how to write code ...
1
vote
1answer
52 views

What is the role of the rightmost transitor in this circuit?

I extracted the following circuit from an schematic. It is part of power section. The switch on the +2V line is actually a GPIO from a microcontroller which turns to +2V when powering on the device. ...
1
vote
0answers
9 views

Unitary property of scattering matrix

From s-parameter lossless network definition , The sum of the incident powers at all ports is equal to the sum of the reflected powers at all ports. But how do we derive the above unitary property ...
-2
votes
0answers
21 views

What's best for separating signal from noise, lock-in amplifier or averaging with digital oscilloscope?

Or isn't there a best one but maybe they are good in different scenarios, say that the noise is 10 times bigger than underlying signal, which one is to be preferred? Similarly, if the noise is say ...
0
votes
0answers
13 views

Laptop battery smbus broadcasting

I connected a laptop battery connector to a micro-controller through SMBUS. I can read information from battery such as state of charge. I listen to the battery broadcasting charging current and ...
0
votes
0answers
12 views

Command from Openocd to deactive Target

Can someone tell me if there is a command from OpenOcd that we can deactivate/stop the Target for a while? I am flashing 4 devices in a daisy-chain with Jtag and OpenOcd. After devices were flashed, ...
1
vote
0answers
10 views

Can I use the transfer function of a servo DC motor as a close approximation to the transfer function of a stepper motor?

I have been trying (just spent many hours on this) to find/calculate/derive the transfer function of a hybrid stepper motor. I don't need an exact transfer function (the electrical and mechanical ...
-1
votes
0answers
89 views

Why these relay issue in PCB? [on hold]

datasheet of relay I have this PCB layout: R >> represent the relays relay are used to switching the load. when all load is active ,relays become hot. ESP module seem to be hot little bit . but ...
0
votes
1answer
19 views

Why double synchronizer alone is not enough for multi byte transfer between two clock domains?

When one bit information is transferred between two different clock domains, we use 2 Flip-flops or double synchronizers. But when we transfer multi bit signals across two different clock domains, why ...
0
votes
0answers
9 views

Flash and debug of multiple STM32 in JTAG with J-LINK

I have a board where 3 STM32 are connected to a JTAG port. The 3 STM32 are daisy chained. I am using a JLINK EDU Mini with Atollic TrueStudio IDE. One STM32F746 is a master for the two slaves ...
3
votes
1answer
256 views

IR receiver - what part it is?

Bought an IR repeater with the simple schematic: The question is, what is this receiver? It looks almost like 4838, has the same pinout, but it outputs encoded signal and I cannot find what is it. ...
0
votes
1answer
42 views

Styrofoam cooler/chest ok for electronics project?

I'm building a DIY power supply using 6 server power supplies. I've been looking for a case/enclosure to hold them and the necessary wiring and came across a styrofoam cooler that's the perfect size ...
-3
votes
0answers
23 views

Mobile gpu for 2x30megapixel~200megapixel 30 fps image processing? [on hold]

I would like to build some hardware to toy with my vslam/odometry algorithm. But I cant decide which gpu should I pick. Anyone may give me a pointer or some kind of good reference? Thanks.
0
votes
1answer
32 views

Garage sensor - in a need of a distance/obstacle detection relay to work for 2-3 m distance

I am building a distance/obstacle detection sensor to detect if it is safe to close garage door already (i.e. car is fully in and is not blocking it, still preserving some space to walk in the rear). ...
-1
votes
1answer
32 views

Simple battery backup

I am experiencing sudden outage in my area from few seconds to a hour or so. I am currently using this circuit. Turning on and off every time for a blackout is just annoying. I just want to cut off ...
0
votes
1answer
23 views

SVPWM: Does setting modulation index to 0 still consumes power?

I've implemeneted a 3rd harmonic injection SVPWM (Space Vector PWM) scheme and it performs quite well. One peculiarity i have noticed was, when i set the modulation index to 0, the motor stops as ...
0
votes
0answers
22 views

vintage amp component popping and crackling [on hold]

Hi i have a vintage pioneer sx-650 recevier when I plug it in I hear a light poping / white noise sound coming from around the transformer area not Shure if it is the electrlitic compassitors or if I'...
1
vote
3answers
69 views

Finding short-circuit across 3.3V power rail and ground rail on PCB

I have a short-circuit between my 3.3V and ground power rail on my assembled PCB. How do I find where the short is? Should I start by removing components one-by-one from the board?
1
vote
1answer
100 views

What this component is?

I'm reverse engineering a pcb but i'm stuck at one component which i cant find out what it is.i thought it is a diode because of the marking on top of it but when i test it with multimeter it behaves ...
0
votes
0answers
26 views

Limit 540 mA CC driver to 300 mA?

I have five 10 W, 34 - 38 V, 300 mA LED COBs I'm wanting to run these in series but to reach the voltage and watt range in the driver, I can only find a 540 mA constant current dimmable driver. I want ...
0
votes
1answer
24 views

Finding the settling time of an oscillatory response

I was reading my book on circuit analysis on chapter about RLC response and became curious about how to get an approximate value for the settling time of the response. Particularly this response ...
0
votes
0answers
11 views

What is T_e in stepper motor equation?

The description for T_e is missing on this page. Source: https://se.mathworks.com/help/physmod/sps/ref/steppermotor.html
0
votes
0answers
38 views

How to allow input on bits of Microcontroller port

I'm trying to figure out this question: Write a line of code in C to allow input on bits 2 through 4 of port A. I am familiar with writing code, I just don't understand the question. Can someone ...
0
votes
1answer
22 views

Exceeding voltage on STM32 Vbat pin

I want to power STM32F429 Vbat pin with an existing Lithium Ion battery on board. However, the maximum voltage on the discharging curve of this battery is 4.2v which is above the maximum operating ...
0
votes
2answers
52 views

Offsetting Voltage from 2.5 V to 0 V without affecting gain

I'm trying to digitize a Hall Sensor whose center voltage is 2.5V and the gain it's output is 1.5V to 3.5V, or ±1V. My digitizing card's center voltage is 0V and I would like to get the full range of ...
0
votes
1answer
34 views

5 V from power bank not constant when supply circuit

Now I'm working on my project which contains Arduino, LCD, electromagnetic lock, 6 channel 5v relay and 500V isolated converter. My project was designed to power by using a power bank. Now I use eloop ...
0
votes
0answers
12 views

How do I wire in a capacitor into an LED circuit to eliminate a flicker issue? [migrated]

I have led running lights on my truck (with a resistor already inline) and am encountering a flicker issue ONLY when the engine is running. I was thinking a cap would fix it.
0
votes
0answers
14 views

+24VDC to 5v converter - does the positive make a difference? [migrated]

I have a fairly general question, but cannot seem to find an answer to confirm my thoughts. I have a garage motor door, and on the top has 4 terminals - 1 and 2 for a switch button to open and close, ...
-4
votes
0answers
76 views

Lead Contamination in house after touching solder [duplicate]

I may have accidentally touched my laptop and keyboard and mouse and maybe my desk after soldering the one time I did and was wondering if it's contaminated with lead and how to clean/dispose of it if ...
0
votes
1answer
43 views

Tripping a circuit breaker when using a half wave rectifier

How does a half wave rectifier or phase control dimmer affect the triggering of a circuit breaker? For example, if a 20A resistive load was on a 15A breaker with a half wave rectifier. Now average RMS ...
0
votes
0answers
8 views

Deriving state table /equation confused

A sequential circuit has two JK flip-flops A and B, two inputs x and y, and one output z. The flip- flop input equations and circuit output equation are JA = BX+B'Y' KA = B'xy' JB = A'x KB = A +...
0
votes
0answers
30 views

Cheap switch alternatives to 9PDT for DIY USB sharing switch

Forgive my ignorance as I am a a sculptor trying to learn as I go. Any direction is welcome. I apologize as I know this question is probably a bit simplistic for this forum. All USB 3.0 sharing ...
1
vote
1answer
24 views

220v universal motor Arduino control

I bought a 220v 100w sewing machine motor to use it in a project Firstly I thought that the motor works only on ac (because there is 220v written on it) and just for try I gave it 30v dc and ...
1
vote
1answer
61 views

Single transistor IR repeater

I need the IR repeater to pass IR (TV and so on) remote signal to remote devices in some box (pass the IR signal from outside the box). So, I bought a cheap IR repeater on single 2TY transistor, 4838 ...
6
votes
3answers
1k views

VHDL: Why is it hard to design a floating point unit in hardware?

Floating point calculation basically involves representing units in a scientific notation and then deciding how many bits to devote to the manitssa and exponent. Therefore, all calculations involving ...
4
votes
4answers
401 views

Which values for voltage divider [duplicate]

I just learned about voltage dividers and how to calculate the relative values for the resistors to use. For instance, to go from 5v to 3.3v I could use a 1 kohm and a 2 kohm resistor. However I could ...
0
votes
0answers
29 views

Replacing a 3-wire piezo buzzer with a relay?

My 9v water sensor alarm uses a 3-wire (M, F, G) piezo buzzer. Instead of a buzzer, I'd prefer wiring a relay to activate a 12v water pump. Is this possible, and if so, which leads should I use? ...
0
votes
1answer
23 views

Down counter using 4510 IC

So i wanted to create a counter that counts from 59 down to 0 using 4510 IC component, so i created simulation in Proteus software. This is what i came up with: This circuit works perfectly fine ...
2
votes
2answers
70 views

Johnson-Nyquist noise for a lossy inductor?

In searching the internet for thermal noise on an inductor and I'm not finding much on the basics for a real lossy inductor. I'm interested in thermal noise for a fixed inductor in a surface mount ...
0
votes
3answers
45 views

Epoxy Resin Molded vs Hermetically Sealed Metal Can Packaging for LEDs and Photodiodes

Between epoxy resin molded vs hermetically sealed metal can packaging for photodiodes and LEDs are there any relevant functional differences I should be aware of when selecting between otherwise ...
0
votes
1answer
47 views

to calculate the voltage divider resistor for transistor

My question is how to calculate the voltage divider resistor (R1 & R2).I have found that Ic=20.8 mA ,hfe=290,Ib=71uA.I'm using the transistor bc847b;the voltage divider network acts as a switch to ...
0
votes
0answers
17 views

Project involving the Texas Instruments TAS5720 amplifier - Power Requirements

The Google Home Mini uses the TAS5720 amplifier with a power supply which delivers 5V DC, 1.8A. From the datasheet it looks like this amplifier can deliver 20 W at 0.15% THD Continuous into 19 V / 4 Ω....
0
votes
2answers
52 views

What will be Resistance for maximum Power transfer from network A to network B?

simulate this circuit – Schematic created using CircuitLab Can we apply Maximum Power transfer theorem if we are given two networks both with voltage sources. In solution it was said that for ...
0
votes
1answer
32 views

How to know when the resault of subtraction is incorrect in a 4 bit binary subtraction circuit?

This is an image of a binary subtractor for unsigned numbers. Some times the output of binary subtraction is not correct and needs to be complemented to give the correct answer, how can I find out ...

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