#Capacitance

[sciencesolutions]

[vbsemi-mosfet]

MOSFET's pull-down resistor serves what function?

MOSFET's pull-down resistor serves what function? (youtube.com)

What is the function of the pull-down resistor on the of a MOSFET?

The pull-down resistor between the gate (G) and source (S) of a MOSFET serves several functions:

1.Preventing False Turn-On: The Miller capacitance, a parasitic capacitor between the gate (G) and drain (D), can cause the MOSFET’s drain-source voltage (Vds) to change from nearly 0 (saturation voltage drop) to the bus voltage when the MOSFET is turned off. This rate of voltage change is "dv/dt." Since a capacitor responds to voltage changes by generating a current, the voltage change across the capacitor generates a current "i."

The gate-source (G-S) junction has an insulating layer, usually silicon dioxide (SiO2), making G-S a high-impedance path (tens to hundreds of megaohms). If there is a driving abnormality, the current through the Miller capacitance can charge the G-S junction. A small current through a high impedance can correspond to a high voltage, potentially charging the gate voltage above the threshold voltage "Vgs(th)," causing the MOSFET to turn on again, which is a dangerous situation.

2.Providing a Discharge Path: In a flyback power supply topology, the Miller capacitance current is discharged through a low-resistance path inside the driver chip, preventing the gate from being charged high enough to cause a false turn-on.

Here, we understand that there is already a discharge pull-down resistor inside the driver chip. However, if the gate resistor (Rg) is open-circuited or not connected for any reason, the external pull-down resistor (R8) can provide a discharge path for the Miller capacitance, keeping the G-S junction of the MOSFET at low impedance for a stable and safe state. This is a critical function of the pull-down resistor.

3.Pre-Protection Resistor: Another function of the pull-down resistor is as a pre-protection resistor. The G-S junction of a MOSFET is high-impedance, which is why it is sensitive to ESD. High voltage applied to the gate is not easily discharged and, over time, can damage the silicon dioxide layer between the G-S junction, leading to device failure.

Therefore, the pull-down resistor balances power consumption and effective discharge. Typically, for low to medium power supplies (0-500W), a resistor value of around 10K-20K is chosen, while for high-power supplies, 4.7K-10K is selected.

That concludes this content! Thank you for your support!

[chipqry]

Circuit board fault analysis: revealing the components most prone to problems

I published an article "Guidelines for Identification and Troubleshooting of Capacitor, Resistor, and Operational Amplifier Faults", article link: https://www.dhsic.com/news/97

[adrin2tonn]

https://www.futureelectronics.com/p/electromechanical--circuit-protection--tvs-diodes/sm712-tct-semtech-1709229

Asymmetrical TVS Diode, USB TVS diode array, TVS diode circuit, esd tools

SM Series 12 V 400 W Asymmetrical TVS Diode for Extended Common-Mode - SOT-23

[sbelectrotech]

SB Electrotech presents the new blog on Capacitance & Tan Delta Test Kit. That explains the role of the Capacitance & Tan Delta Test Kit. Please go through this blog.

[lambouillet]

I'm just curious, genuinely--what is it about Narilamb you don't like? Is it because it's popular, or do you just not like the dynamic/have a different ship you're more prone to liking?

OH you would not like me if I told you anon. Those two things are by far the least and most benign of what I genuinely think of it 😁 but ive chosen peace so you're not gonna hear any of it for now. Thats just how it is i fear.

I don't mind it anywhere else just the more ive thought about it personally the more ive come to dislike it. If its not in the context of a joke then its not something I'll be making.

[screamingapetheory]

btw i dont know if anyone's posted this yet but if you manage to survive the knight's wind tunnel sword assault at the beginning of the ch. 4 dark world you actually get a unique cutscene for doing so

[80smovies]

[ggstudyblr]

notes ft. my emotional support claw clip :P scans attached below

just trying to catch up. my prof tells us to print the lecture powerpoints so we don't write as much but idk how I feel about it.

excited to write these! my s/o got me a big pack of mildliners <3 so I wanted to test all of them

[sciencesolutions]

[fullbrave]

i'm sure this crossword clue is some kind of easy obvious answer for people with electrical knowledge but for me it feels like reading a fire emblem heroes skill description

[b4kuch1n]

ough brain is doing SO bad but sometimes. there are colors

[socojes]

The working theory of the capacitance level sensor(CLS) uses capacitance that is created by liquid that fill in the positive and negative probe. With the change of the liquid level, the change of the capacitance will be converted to standard electrical output signal. The main component is the highly-integrated capacitance chips, by the exact temperature compensation and linear correction, the sensor has the advantage of high accuracy, high stability and continuous measurement.

[the-acid-pear]

Went for a walk but instead of touching grass I started thinking of phones and man I'm so fucking Curious and Hyped to see the Roger route especially to see how different he is from his counterpart in DSaF.

After all, in that universe it really seems that the only thing that made Roger get his shit together after his wife left him and he dropped off med school and shit was fucking Dying and getting to now be Someone Else (see: Scott) but now everyone is already a phone so that possibility is off the table which makes me wonder, is this Roger just not miserable or is there a brand new thing that he found to get his life relatively together?

[xxplastic-cubexx]

the RESIST thing is from fall of x and the hellfire gala 2023 (maybe it was established earlier) when Charles sends all the krakoans through the gates but he taught some of them this mental block/defense aginst attacks like that's also called the red triangle (i think) and we see it as a triangle of the word resist in red

Just casually repping peak…….

[ihatenamesapple]

*Throws this at tumblr and hides again*

Happy late demyx day yeyyy