Questions tagged [protection]
Ancillary circuitry that protects the main circuitry in case of a fault. Examples of faults protected against are: overvoltage, ESD, overheating, and overloading (too high of a current draw). In some cases the protection circuitry is sacrificial, being destroyed or degraded in the act of protecting.
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What measures should I take to protect the USB ports of my PC during development of a USB device?
I'm going to start developing a USB 1.1 device using a PIC microcontroller. I'm going to keep one of the USB ports of my PC connected to a bread board during this process. I don't want to destroy my ...
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Understanding an 'ideal' diode made from a p-channel MOSFET and PNP transistors
The Raspberry Pi B+ models have a protection circuit between the USB connector and the 5V net on the board. They recommend putting a similar protection circuity on a Pi HAT before 'backpowering' the ...
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Correct use of Flyback or Snubber diode across Motor or Transistor?
From seeing a few schematics where the flyback or snubber diode has been placed across the transistor C-E terminals (Right Configuration), instead of what I typically seen as the the flyback being ...
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Reverse polarity protection
I read somewhere that this can be used for the reverse polarity protection in the circuit. But I am quite confused with its operation. Can somebody help me with this.
simulate this circuit – ...
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Scam? Does having this capacitor wired as shown provide any surge protection?
Bought this on Amazon as a dryer 240V SPD. I was trying to find out if this device is an outright scam. I found a similar post on here from several years ago but that did not answer my question. ...
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OR-ing power supplies (diode or mosfet)
I have got two power supply options on my board:
USB 5.0V
DC Power Jack of 5.0V
My intention is to design a or-ing power supply option, as either of them will be used at a time. Possible solutions ...
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How diodes protect H-bridge DC motor driver?
I don't really understand how these diodes in this circuit and similar circuits (like driving a relay circuit) protects the controller circuit from the energy stored by the inductance of the coil.
I ...
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Lithium Battery Protection Circuit - Why are there two MOSFETs in series, reversed?
I was studying a battery protection chip and reference circuit (below) commonly used in cell phone Li-ion batteries, and am confused by the two MOSFETs in series on the negative terminal EB-.
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What is "foldback short circuit protection" in a power supply?
I am looking at buying a 24V power supply. Two of the options are these:
PSP24-060S 24 VDC 2.5A (60W) power supply
PSB24-060-P 24 VDC 2.5A (60W) power supply
The first offers "foldback short circuit ...
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How does a diode clamping circuit protect against overvoltage and ESD?
I always see this circuit when talking about overvoltage or ESD protection (does this circuit accomplish both, or just one?):
However, I don't understand how it works. Say I put in 20V at Vpin.
So ...
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Regulated Joule Thief: why it works?
Please explain to me why this circuit can give me a regulated 5 V? I understand the Joule Thief part, but why the regulator part work?
simulate this circuit – Schematic created using CircuitLab
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Circuit to protect against undervoltage?
What is the simplest way to regulate the min DC voltage in a circuit?
Is it possible to do with zener diodes?
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Does an over voltage, over current and reverse polarity protection IC exist?
I'm designing a circuit that has the following protection requirements:
Reverse polarity
Over voltage (60v max)
Over current (approx 1A)
There's quite a large input voltage range, 10v to 60v.
48v ...
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What happens after a zener diode breaks down?
I've strapped a 6V zener diode across the 5V/GND rails of my circuit, and I want to know what will happen if my supply were to somehow fail pass 12V straight to the rest of my board.
The zener will ...
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Optocoupler input protection
I have to provide some isolated inputs that accept 12-24V. There should be some protection against reverse polarization, transient over-voltage and permanent over voltage (up to 40V) to some degree.
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