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 do the following parameters indicate in a resettable fuse?
I am not sure how to decipher the Pd and R1max info in the below datasheet.
Does PD indicate the tripped state power dissipation or maximum power dissipation under non-tripped operation?
If you ...
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What is the criteria to choose between PTC thermistor and resettable fuse (PPTC)?
Wiki states:
(PPTC) are similar in function to PTC thermistors in certain situations but operate on mechanical changes instead of charge carrier effects in semiconductors.
Another wiki says there is ...
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DC Bias network for a LCR meter
I am trying to make a DC bias network for my LCR meter (Scientific SM6023) based on this circuit I found online
RD10E has a Zener voltage of about 10V and 1N4004 has a forward voltage of 1V. I have ...
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Dual Rail Reverse Protection Circuit for OP AMP inputs
Is there a way to resolve this? When wrong polarities is applied,then I wanted no voltage or current flowing towards the OP Amp. Thanks!!
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PSPICE non sinking voltage source
In an ideal world, most power supplies have a current sourcing feature but not a sinking feature. In this circuit, you can see that the 15V supply is sinking current. How can I prevent this in Pspice?
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Arduino Uno ESD ruggedness
I want to route one of the Arduino's digital output pins out of a device, to interface with other instruments via a several meter long coax cable. Typically, I would implement measures against ESD for ...
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Issues with AP9101C Lipo protection IC and the auto-wakeup feature
I'm developing a pcb for a product powered by a single-cell li-ion battery. Since I couldn't find an appropriate battery with a built in protection ic, I decided to add one to my design. After ...
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Ferrite bead value for a LIN bus protection circuit
What is the proper value for FB1 in relation to the surrounding capacitors in this diagram?
The FB1 resistance is measured to 0.76ohm and package size is 0603. All components are AEC-Q200 rated.
The ...
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Auxiliary mechanical anti-ESD measures
If a PCBA within a plastic enclosure is prone to malfunctioning due to ESD air discharge in proximity of enclosure seams and openings, but changing the hardware or plastic design is not an option, ...
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Is it OK to have two protectors for a single Li-ion battery?
I have a question regarding a Li-ion charger/protector module. The board I'm using a fairly standard Li-ion charger/protector module.
This module manages the charge using a TP4056 IC and has a built-...
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Reverse polarity protection + inrush current limiting with mosfets schematic
What do you think about this schematic? I want to put this before a DCDC 24 to 5V with maximum 1A. Any comments or suggestions? The aim of this circuit is to have a soft start with the resistor R2 in ...
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Residual current relay continuity
Even if the leakage current relay is 300 mA, it cannot provide human protection in such a case. Then, if I make a circuit like this, if there is already 270 mA leakage, then if there is an extra 30 mA ...
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Litium Battery Series-Parallel 2S2P Protection
I am designing a PCB which has 4x Primary Lithium cell Batteries (ER14505M) two in series and two in parallel to give 7.2 V 4400 mAh. The cells have their own holder so it would be possible to only ...
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Reverse polarity protection and inrush current limiting - back to back mosfets
I was testing this circuit in LTspice, it would protect my boards from reverse polarity and limit the inrush current to the input capacitor of a DC-DC (buck or LDO),
but the simulation gave me this ...
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How should I layout an optocoupler isolation board with separate ground references and power supplies?
I am thinking about how to layout my opto-isolation board. It is used to protect pins on an FPGA, convert signals to RS-422 and then transmit via RJ-45.
I have seen some conflicting information about ...
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