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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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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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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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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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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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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How do I protect against an automotive load dump?
A load dump occurs when the load to which a generator is delivering current is abruptly disconnected. In automotive electronics, this applies to disconnecting a battery while it is being charged by ...
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MOSFET in reverse polarity protection
I have such a reverse polarity protection circuit for the power supply:
The MOSFET used has a maximum VGS of 10 V, so that's why there's a Zener diode of 7.5 V.
But what happens if I ...
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Protection against automotive power supply hazards
I'm looking for a way to protect a small circuit which is to be used inside of a car or truck (12V or 24V power system). The circuit consumes about 12-15W. I use an isolated DC/DC converter module ...
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Reverse polarity protection - PMOS vs Schottkey diode
I have a circuit running from 2 AA cells in series, meaning I get 3.0V when fresh (or 2.4V if NIMH cells) and it goes down to 2.0V, that's when my circuit cannot function anymore (no DC/DC onboard).
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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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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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Over voltage and reverse voltage protection of multiplexed ADC with voltage follower
I am designing a protection circuit for the ADC section of a design I am working on.
There will be 8 analog signals being read by a single pin of the MCU via an 8 channel multiplexer. The analog ...
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Reverse polarity protection idea
I'm thinking about making a reverse polarity protection for a project. This is for a small line follower robot and I'm still deciding if I need a reverse polarity protection at all.
It will be powered ...
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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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