All Questions

0
votes
0answers
6 views

Immediate Rain Detector

The Problem: I tend to open my bedroom windows so that the natural breeze can pass. This is great for cooling but not great when rain falls. If rain falls heavy enough, even if it falls for 1 minute ...
1
vote
1answer
6 views

Is there an economical 2-3 RPM 120v motor with speed control? Or what components could I use to achieve that scenario?

I've got a mechanical design for a piece of catering equipment and I need to figure out a way to achieve some variable speed control for a slow RPM motor. This is a direct drive application (imagine ...
0
votes
2answers
20 views

Fusing electronic platforms into one IC board

I have an insane goal whose possibilities id like to discuss. To start with I am interested in three different electronics platform for edge computing: Edge computer: Like Raspberry pi or Intel ...
1
vote
2answers
28 views

Working on a design that requires a specific kind of physical switch

The switch my design needs behaves like the picture below. The user would slide the switch to the right to activate it and the switch would return to the left automatically, I assume by some kind of ...
0
votes
0answers
11 views

how the battery behaves in this diagram

My question is this. I'm using this ic mppt SM72445 along with a 250 watt solar panel, mppt output configured to 50.4 or 51 volts, 12-cell lithium-ion battery pack and bms, if the load is less than ...
1
vote
1answer
34 views

What are the ways to automate work of an electric motor? [on hold]

I need to develop a system which can make an electric motor to run for 3 second and run reverse for another 3 second and do this cycle for continuously and automatically for days. The motor should be ...
0
votes
1answer
46 views

What kind of plug is this?

I'm trying to figure out what type of plug is this. According to this site it is most similar to type A, but the blades are spaced only 10mm apart and they have the same size. According to here one ...
0
votes
2answers
29 views

Is there any physical limitation to cell carries sharing the same frequency?

Currently in the U.S. certain companies are granted leases on certain frequencies for cell phone communication. I was discussing with a friend how this allows a company with a lower frequency to get a ...
0
votes
0answers
22 views

I have a motherboard with HDMI output. What display for it needs I2C or SPI or another? [on hold]

How i can check compatibility? What parameter is responsible for this? I want to connect the display (for example from smartphones phones). I want find it on stores, but i dont know what will work.
0
votes
0answers
27 views

How make a pulse acquisition from an electrical meter directly into a raspberry pi?

I would like to acquire pulse informations from a french electrical meter. There is a picture of the outputs of this electrical meter. These pulses vary in frequency and after acquisition, we can ...
0
votes
1answer
56 views

How to measure this component

I want to know how to measure this components in the attached picture. If I'm right they are beads. The second one the brown one I thought at first that it is a capacitor but I can't measure its ...
0
votes
0answers
30 views

Solid State Relay is giving off voltage even when turned off

I'm currently creating a circuit according to this schematics i made. I have removed some irrelevant parts for simplification sake. The SSR in question is a 861SSR210-DC-1. When 5v is applied between ...
-3
votes
0answers
28 views

Current consumption by 3-6V DC water pump [on hold]

If I use a submerisible pump of 3-6V DC and interface it to a controller via L293D. What will be the current consumption by pump? How should I calculate it?
0
votes
1answer
56 views

What are these tiny ports on my usb internet dongle? [on hold]

My vodafone usb internet dongle has these two tiny ports in the side with two small covers with a tower symbol on it. Are these by any way antennae connection ports?
1
vote
1answer
63 views

Matrix of small incandescent lightbulbs - problem with buzzing

I am prototyping a circuit for controlling matrix display of small incandescent lamps with Arduino (each lamp is 6.3V 0.3A). I designed the circuit in Yenka and built it. It is composed from 3 types ...
2
votes
2answers
93 views

What does this symbol on the box of power supply mean?

I always see this symbole behind electronic devices. A close-up image of the symbol: What does it mean?
2
votes
1answer
25 views

Hybrid library vs normal one

We use Orcad and we want to update our libraries. When we place a part and want to rotate it,we don't like the layout of the labels(names,values etc) and thus have to manually reposition them. It's ...
0
votes
3answers
92 views

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 ...
-1
votes
1answer
33 views

Is it convenient to use a buck converter on a RS-422 communication board?

I am working on a PCB design with STM32 MCU. On the PCB there will be 2 MAX490 transceivers and one bluetooth module. Communication speed will be 921.6 Kbit/s for all communication elements. ...
1
vote
4answers
92 views

High resistance, no current. What's the point of a potential then?

I am referring to this example: Why does it matter that the IC has a high resistance? What does this do for/to the IC? If there is a potential but no current, what is the point of using the IC when ...
0
votes
0answers
65 views

Why does this laptop adaptor have two metal shields with different thicknesses?

Yesterday, I opened my laptop adaptor to learn something. First off, faced to this kind of shielding: There are two shields that cover the circuit. A thick shield which is covered by a thin shield ...
0
votes
1answer
38 views

Where better to pull the NTC thermistor? To earth or VCC?

I have a NTC thermistor, resistance 10k. In various examples, thermistors pull either to the ground or to the VCC. The question is, is there a difference and what is safer?
-1
votes
0answers
21 views

How to constraint clock on the GPIO of FPGA

I want to implement the JTAG protocol with Verilog HDL in FPGA. The TMS and TCK signals are all connected to the GPIO pins of FPGA, not to the dedicated clock pin. TCK's rising edge is almost aligned ...
0
votes
2answers
23 views

Vector Control & Slip

I know slip in induction motor determine the current and torque but the point I want to ask, when controlling with vector control it is said stator and rotor flux is always kept with 90 degrees apart ...
1
vote
1answer
55 views

Is this IR LED driver circuit with a transistor OK?

I am making a custom IR array board with a custom Arduino (only ATMEGA328 and necessary components.) So please tell me will this be fine or if I need to make some changes. IR LED = 940nm, continuous ...
1
vote
4answers
53 views

How to use libraries with delays inside within a time critical STM32 HAL application?

I want to use a library for an LCD for STM32: LiquidCrystal, and possibly some other libraries. I noticed this library is full of HAL_Delay calls, not only during initialisation but also during ...
0
votes
0answers
35 views

Shockley equation for diode series

I'm currently using the Shockley equation and a Newton-Raphson solver to find the current of a diode. I remember there's a variation of the Shockley equation that can be used to calculate two diodes ...
0
votes
2answers
69 views

Connect 10 LEDs using 5 volt current

I have 10 yellow-colored LEDs and ten 220 ohm resistors. I don't have any power source except the Arduino's 5 volt itself. Is it possible to power all the 10 LEDs using the 5 volt equally? Or will ...
0
votes
2answers
65 views

Design a Circuit with Zero-Order Transfer function H(s) > 1

I know that if I do 2 1K ohm resistors in series, I can just do a voltage divider to get Vout/Vin = R2/(R1+R2) = 0.5. But if I want to get a transfer function of 3, what components would I use?
1
vote
1answer
52 views

Probing with oscilloscope causes current drop

We are testing a fabricated chip with expected output current of around 4mA which is then used to charge a button cell. The input is from a PV cell. However, when we attach an oscilloscope probe onto ...
1
vote
1answer
41 views

Output impedance of a series shunt feedback amplifier

I am trying to find the output impedance of a series shunt feedback amplifier by converting it to a two port network. I know the input impedance: Ri=ri*(1+A.β) But I dont know how I should find ...
0
votes
2answers
48 views

how a battery behaves in parallel to the charger with a shared load but with a voltage difference

how the battery behaves in this diagram how a battery behaves in parallel to the charger with a shared load but with a voltage difference
0
votes
3answers
56 views

Transformer question regarding efficiency

Due to the question being discussed in length on the comment section, I would like to address my question further with a new post linking from the discussion here: Transformers confusion with output ...
0
votes
0answers
37 views

Joule Thief Modelling

I Try to use a joule thief circuit to harvest energy from almost die battery. But the reference that i found on forum or conference paper just explain how joule thief circuit works, not the ...
0
votes
2answers
28 views

Can I use a 555 PWM signal to control

I want to use a 555 PWM signal to control a motor. I also want represented the speed of the motor with an LED graph using a LM3914 led driver. Can I use a digital signal to control the LM3914 ...
4
votes
1answer
158 views

Difference Between RMS noise and PSRR in an LDO

I am trying to choose a low dropout linear regulator to partially smooth the output of a dual rail SMPS I'm using to power analog circuits. I'm confused about the difference between the specified RMS ...
-2
votes
1answer
38 views

What is the corresponding MIPS code?

Assume that variables f, g, h, i and j are assigned to registers $s0, $s1, $s2, $s3 and $s4, respectively. Also, assume that the base address of the arrays A and B are in registers $s6 and $s7. ...
0
votes
0answers
31 views

Splitting a power supply to two monitors

I'm working on a project that requires 2 (identical) LED monitors, each of which has a separate power supply that outputs 19V 1.3A. To save space, I would like to instead use a single power supply ...
0
votes
0answers
11 views

Ratio between RFID reader and tag antennas

If a tag's antenna (45mm x 75mm) is larger than the reader's antenna (20mm x 26mm), could this pose coupling problems when trying to read the tag? The reader functions correctly with tags similar to ...
0
votes
0answers
27 views

On-board st-link programmer on F411 Discovery board cannot connect

Backstory: I have STM32F411E-DISCO board which has on-board st-link which i used before without problems (also programming external stm's). Today i tried to program STM32F103C8T6 with SWD connector (...
-1
votes
2answers
40 views

Ideal 24V DC to DC 5V Converter just to feed 556 IC

I'm trying to find a best match for a regulator that can feed dual timer ic. The 5V circuit is dedicated to that IC which will generate a PWM pulse signal to PWM control the FAN speed. It's a 4 pin ...
2
votes
4answers
345 views

N-Channel Mosfet as Switch

I have a few n-channel MOSFETs (the irlb8721's) and I was able to use it as a switch to control an led with the gate at 5 volts. I would like to change the source/drain voltage to 11.1v from 5v and ...
1
vote
2answers
75 views

Four Layer PCB doubt

I was looking a raspberry pi zero board, and I think it is four layer pcb, but I dont understand now why the designer used a ground plane on top and bottom layer? It is assumed the four layer pcb has ...
0
votes
2answers
39 views

Adequate Power Supply for 300 Daisy-Chained LEDs

I have 300 LEDs (ws2812b) wired in a series. They were sold as 150 LED/5 meters and rated to power at 9W/m, so 45W/5m strip. I would need 90 Watts to power my entire 300 LED strip. I have a 3-rail ...
-6
votes
1answer
38 views

4 bit Binary Divider Circuit

We are making this 4bit binary calculator project but sadly our divider circuit didnt worked. Can you give me some schematic for 4bit binary divider? Thank you.
0
votes
0answers
52 views

How to clean circuit damaged by bleach?

I was trying to remove stains on a fiber optic party tie using bleach, however it seems a small quantity has leaked inside the controller overnight, causing some corrosion and preventing it from ...
0
votes
0answers
40 views

Is my assembly code in MIPS correct?

I've started studying assembly, and I'm trying to solve this problem: For the following C statement, what is the corresponding MIPS assembly code? Assume that the variables f, g, h, i, and j are ...
0
votes
3answers
68 views

Can someone explain this constant current load circuit?

I'm currently a rising junior in EE and I was just wondering if anyone could help explain this circuit for me. The purpose for this is because I need to learn how to build a discharger (constant ...
0
votes
3answers
65 views

Emitter OR rather than diode OR

I'm building a power supply for a product that uses a 5V regulator if external power is connected or three alkaline cells if not. I don't want to waste half a volt or more from the cells by diode ...
1
vote
1answer
22 views

Adequate Power Supply for 300 Daisy-Chained LEDs

I have 300 LEDs (WS2812B) wired in a series. They were sold as 150 LED/5 meters and rated to power at 9W/m, so 45W/5m strip. I would need 90 Watts to power my entire 300 LED strip. I have a 3-rail ...

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