Trending questions
213,345 questions
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Split power supply design
I'm designing a power supply with both negative and positive power supply rail. The voltage source shown in the schematics is actually the output from the secondary of a flyback converter transformer. ...
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1
answer
45
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Single ended supply Class AB push-pull amplifier
I have a basic Class AB push-pull amplifier that uses diode biasing for the transistors. The circuit operates from a single-ended supply (e.g., +VCC and ground), and the input is a sinusoidal signal ...
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Circuit design active filter design [closed]
Circuit design
Band pass filter
Active filter
Multisim
And find their objective circuit analysis
2
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4
answers
241
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Transformer core design without number of turns available
I have to design a transformer with defined parameters such as my primary and secondary voltage, rated power of the transformer, the flux density and the lowest frequency \$f\$, are there other ...
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0
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determine the transfer function of this modified instrumentation amplificator
I'm trying to get the transfer function of the circuit, I get the instrumentation amp part but later I got stuck again in the the inversor plus the last one (sum point?).
Started with the next section
...
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1
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42
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Different resistors needed depending on output? (HC-SR501 PIR sensor)
I am assembling a proximity/motion activated night light using a dpdt 6 prong, 3 position switch (on/off/auto). When set to on, I expect the full voltage (5 volts or so) to pass through the switch, ...
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1
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67
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How to Keep Track of Boards and What is On Them [closed]
Does anyone have a good system for keeping track of boards and what is loaded on them? For instance, if I have 10 Pi or Arduino projects going, I would like to label which board is which. And there ...
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0
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42
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Raspberry Pi Pico not displaying image on ST7789 SPI display [closed]
I am trying to connect an ST7789 SPI TFT display to a Raspberry Pi Pico (RP2040), but the display stays blank (black screen).
What I have done:
SPI is enabled
Power supply is 3.3V
Wiring is as ...
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1
answer
106
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Mistake using multimeter
I don’t know if this is the right place to post this question. If it isn’t, I’m sorry!
I was using my uni-t multimeter to measure voltage between the neutral and ground wires in an outlet, because I ...
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1
vote
1
answer
72
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DP83825I reports 10M in PHYSTS register while link hums along at 100M
I am driving a Texas Instruments DP83825I (10/100M Ethernet PHY) using an STM32H573 with firmware I am writing (see output below) on a custom board. So far as I can tell, the board is good (750M pings ...
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6
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2
answers
328
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Speaker repair / unknown inductor/ferrite bead on speaker PSU
I'm repairing a speaker power supply (KEF LSX), and I'm trying to find a replacement for component L802 (see arrow), this is either an inductor or ferrite bead, but I'm not fully sure.
The primary ...
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3
votes
2
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495
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Who updated the symbols for MOSFETs and when did it happen?
This is a question about the history of electronic symbols and standards.
I'm finally starting to learn how discrete devices actually work from the entertaining yet incredibly insightful and ...
- 3,556
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votes
0
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26
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dp83825i PHYSTS register doesn't report link up until BMSR is read
I am using the following firmware function to detect link up on a Texas Instruments dp83825i (10/100M Ethernet PHY).
...
- 814
-1
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0
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57
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Using two power sources on a single solenoid?
We have a lock that is controlled by a solenoid. The solenoid locks the door if the power is off, and unlocks the door when it receives power.
We are hoping to hook up two sources of power to this ...
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3
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3
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231
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Determine Target Voltage for Pre-Wired LED
I have a number of pre-wired LED's that I purchased in the past (see picture) but don't know if they are 5V or 12V (I've purchased both), and I'd like to sort them out. How can I do this?
There is no ...
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