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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3 pin Gas Discharge Tube (GDT) - pinout order
I would like to know the reason behind the pinout order of a 3 pin GDT.
GDTs are designed to prevent damage from transient disturbances by acting as a “crowbar” in creating a short-to-ground circuit ...
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One-Way charging connector for 4S Battery
I want to use a connector to charge the 4S Battery of my underwater robot. The connector is the 6 Pin hybrid Cobalt Series connectors from BlueTrail Engineering (https://www.bluetrailengineering.com/...
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How to prevent this op-amp from railing
I have the following circuit:
An input that can go negative (+/-5 V sine wave), and two inverting op-amps. The second op-amp is "current buffered" and is driving the base of a BJT.
Here is ...
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What are the meaning of the simple directional arrow above the double arrows in this schematic?
Helo,, I would like to know what are the simple directional arrows above the double arrows in this schematic?.
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Protecting negative power rail
I don't trust my power supply and want to protect my circuitry from over(under)-voltage, but cannot find a clear path of going forward with negative power rail. LDO which I use (LT3094) is rated for ...
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Risks of placing Varistor before Fuse for Mains Voltage
I have seen many questions on this and other forums asking about the best option to place the fuse relative to the varistor to protect it from mains voltage spikes and the answer was unanimous: The ...
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How to select ESD TVS diode? [closed]
This is the following specification of my circuit
Vin 8V to 32V
The breakdown voltage should be 33V of TVS
I don't know what clamping voltage means please simplify it for me
What should be Vc?
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Protection from live casing without true ground
I guess my question is probably trivial with an expected answer like 'It couldn't exist and would be dangerous', but still I keep it around.
Could you build a protection circuit that would protect a ...
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How does a voltage surge/spike affect the wall wart power supply's secondary side?
In the photo, you can observe an old-style adjustable wall wart AC to DC power supply, typically composed of a primary winding, secondary winding, rectifier, and capacitor. If a voltage surge or spike ...
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BJT B-E Zenering: whither the collector?
So, I'm trying to analyze how the circuit in this question behaves when subject to reverse battery (vs. being driven from OUT to IN), and I'm running into a severe snag in the process, though. It ...
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How is SM712 TVS array suitable for use with MAX485 in an RS485 driver circuit?
I have an RS485 driver circuit consisting of a MAX485 driven by an STM microcontroller. I was looking at TVS diodes for basic protection from electrostatic surges from wiring and handling, and found ...
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Operation amplifier input HV protection
I have a setup consisting of 8x AD8428 ultra-low noise opamps on a PCB to measure very small voltages with a noise floor of around some 100uV and a low-pass filter up to 10kHz. The input is connected ...
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Mains transformer input overvoltage protection
You have a mains transformer with switchable inputs, 120V and 230V.
In case somebody switches the input to 120V and applies 230V (which cannot be mechanically prevented, reasonably), the whole ...
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What does the graph 'Short circuit monitoring interval Vs time' mean in this SSR data sheet?
In one of the Panasonic Solid State Relay (SSR) datasheet,the short circuit behaviour is as shown below :
If short detected- > Trip the relay -> Periodically retry untill the fault is cleared.
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Not able to correlate the graph and table for the I2t rating in a fuse datasheet
In the datasheet, the I2t rating of a 5A fuse is 0.055 at 10 times In.
Using the same value to estimate the trip time for the 10 A condition, I get 0.0022 seconds. In the graph below, it comes ...
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