How does a Bootstrap gate driving circuit work? Bootstrap MOSFET gate driver technique

[@botak333]

Hi sir i have ir2104 its not workng, when i chek HO its output is 12v as a input vcc, but the LO without outut. I used two ir2104 as a fullbridge, but when i put SD pin low the HO will 0v and LO is 12v sir, i search that like a fake ir2104(its like a ir2103) but when i try to make the sircuit for ir2103 same not working sir. Do u have solution? I change bootstrap already

[@yunusemreozdemir1342]

I am really grateful for your teaching us this topic. Thanks for your effort. However, I can not understand the level shifter part. Could you tell us it here?

[@VisheshSingh-x1g]

Timestamp 4:02, can you please explain here a bit more, how High Side mosfet can pull VS to High Voltage while it is turn off? Please the IC Part Number.

[@martinsiolowosoran5242]

Please i need your assistance. I use ir2104 but the high side is not switching, please what can i do

[@sleepyjaguar]

Same issue. Tell me if you overcome this problem

[@عاشقاللغةالعربية-ق1ش]

can i use ir2153 integrated circuit? Are you running igbt?

[@arefmohammadzadeh8560]

very good explanation... thank you.

[@restybarcia8565]

So can we just slap a 12v or 15v on the high side supply, an (isolated psu) instead of bootstraping.?

[@mrkbsofficial5651]

How capacitor is working in dc ?

[@fmdj]

In the manufacturer datasheet I have for IR2104 they have the cricuit you describe but they put a capacitor between the drain of the top MOSFET and the source of the bottom one, is that to mitigate that negative transient you're talking about? I'm not sure to understand that part. Neat video otherwise thx!

[@Emcontroller]

Please suggest a best mosfet gate driver circuit for a bldc motor controller application

[@عاشقاللغةالعربية-ق1ش]

Is there isolation between the ground inside the integrated circuit 2110 ؟؟؟؟

[@FoolishEngineer]

no

[@shrikhursade9655]

wha if i directly fed supply to drain of high side switch

[@alcatrazgaming8958]

Well if we increase the bootstrap capacitance (lets say 1500uF,as i have made a h bridge mosfet motor driver and was quite successful)then the duty cycle can be 100% for longer time

[@pastaman6099]

You can protect the capacitor and the high side mosfet gate from over voltage with a zener diode, say 15V. Vdd can be much higher then.

[@jaesungoh4595]

can I ask one? how can we prevent negative Vs-Gnd voltage? some gate drivers break when the motor's common voltage is negative.

[@rafalzasada8826]

Correct me if I am wrong but my understanding is that because of the diode of low side transistor the lowest negative voltage on VS would be -0.7V. Is it really a problem for bootstrap capacitor?

[@FoolishEngineer]

No. It will be 0 wrt to gate

[@honorbean2973]

Yes, when the HS FET turns off, the freewheeling body diode of the LS FET turns on due to the inductor current. The VS pin will be one (body) diode drop below ground. The body diode isn't a perfect Si PN diode and the forward voltage drop Vf is usually greater than 0.7 V. So likely a little more than 0.7 V below ground. You have the right idea.

[@rajendranayak2194]

i am new to this . how load will on

[@FoolishEngineer]

When the current flows

[@kaesham7929]

what happen if the high side mosfet is turned on first, in that case the capacitor wont have any charge right, so will that hinder our usage or consequtive cycles will clear this problem

[@riccardodellorto4267]

It is designed in such a way that during the on period you put a charge Q in C, and in the off period the capacitor can't lose more than Q. Eventually, you'll reach a regime condition where C is charged and the mosfet turns on. You need to precharge the bootstrap capacitor before turning on the high side mosfet, but it doesn't matter if the first cycle is "on" or "off"

[@fhxhx]

This circuit used in computer motherboard with 3 circuit in parallel,but I can't understand one single lower mosfet and inductor getting too hot, but motherboard working properly

[@lazypanda-lp]

the video was very detailed and helped a lot, but is there any way to apply bootstrap circuitry on high side mosfet without using IC?

[@riccardodellorto4267]

Yes, you just need to apply a pwm to the ls gate. The circuit is a bit different as well

[@tyronearendse1722]

Hi friend thanks for the informative video

[@FoolishEngineer]

Thank you too

[@Dc_tech386]

I am using a 555 for my inverter project but I cant get the high side to turn on and off Respect to to low side the low and high or turning on at once and short circuiting I use the bjt to slip the signal for high side switching and a puchpull for amplifier current but for some reason everyone KZbin video I side this design work but my same design refused to work just shorting out and blowing up mosfet because am use high volt 24 volt I try using a optocoupler but am getting the same results shorting out so am asking why the bjt amplifier transistor and the low side from the 555 Itself refused to work I checked the circuit over and over to make sure it’s the same at the diagram and it is but still results to work high and low but turns on at the same time

[@TheDesai1234]

You are awesome ..!! I love all your content… very technical and detailed explanation..!!

[@FoolishEngineer]

Thank you so much 😀. Please subscribe to our channel

[@electroquests]

Very well explained!

[@electrowashyelect9715]

What is the effects of having large value for the boost strap capacitor

[@riccardodellorto4267]

Once it has reached the regime condition, it takes a long time to lose its charge in the off phase (which is a benefit)

[@Pythonclcoding]

Can you make a video on dead time for half bridge ?

[@FoolishEngineer]

kzbin.info/www/bejne/pqenlHuqm9BojNk Please check this video. I think it will help

[@satasauu757]

How can we make the gate pin negative 9 volts while the MOSFET stops conducting electricity? Help me make a video thank you.

[@anirudhraghunath5901]

Having a issue when using a bootstrap half bridge driver using IR2101. Expected- During the deadtime interval where the high side must turn off and low side turn on after the dead time. What's happening- when the dead time starts, the high side switch still conducts with Vg= Vs= Vbus ( not VG= Vbus+Vdd). After the dead time is over the high side MOSFET switches off completely. This dosnt happen during the turnoff of low side MOSFET which turns off immediately when dead time starts.

[@salvatorebarbaro5862]

IR2101 not have anti cross conduction circuit

[@anirudhraghunath5901]

@@salvatorebarbaro5862 i am giving dead time to to complimentary pulses through microcontroller input

[@salvatorebarbaro5862]

@@anirudhraghunath5901 yes is this the rigth way

[@salvatorebarbaro5862]

ir2104 is obsolete IC, find IRS2184 / IRS21844

[@anirudhraghunath5901]

@@salvatorebarbaro5862 I'm not making a product, it's for research, hence I have a stock of IR2101 which is DIP with independent inputs

[@danielsaturnino5715]

Wow, very well explained. Thank you

[@FoolishEngineer]

Thank you so much! Please show support to my video with Super thanks and don't forget to subscribe to our channel

[@cnccontroller]

Excellent! Fine! Thank you! Very interesting!

[@FoolishEngineer]

Glad you enjoyed it!

[@vkproduction1166]

Hi sir I love you video I have one question if I need to switch high side mosfit I need to give high signal to ic's (HIN pin ) If i need to switch low side of the mosfit I need to give high signal or low signal to (LIN pin ) ??

[@FoolishEngineer]

you need to give high signal to LIN pin

[@Yorumcu63]

Excellent video

[@FoolishEngineer]

Thank you very much!

[@sudheerkumar5966]

Very very good vedio

[@oscarlara122]

Excelent explanation 👏. I have a question, Is it possible to apply a 0V signal (not pwn) to the LIN input and a PWM signal to the HIN input?. Or you must have a complementary PWM to charge and discharge the gate-sourc capacitance of the MOSFET?.

[@FoolishEngineer]

you must have a complementary PWM to charge and discharge the 'Decoupling capacitor' to drive high side MOSFET

[@oscarlara122]

@@FoolishEngineer thanks mister for your answer. Saludos from México 🤟

[@shiv8144]

@@FoolishEngineersir please help In my pcb also there is a Pwm and gate driver IC and 02 mosfets And the problem is that mosfets are getting defective again and again after replacing them

[@sandeeppinninti3087]

Thank you 🙏

[@ramu1020]

Good explanation, Could you please make a video on DC link capacitors for H bridge driving motors

[@FoolishEngineer]

okay

[@subash001s]

Sir pl make a video on IR2104 with full wording PWM signal bcz if u scarch on net it show many circuit diagram but I want the correct one thatyyou can only do

[@FoolishEngineer]

Sure! I'll try

[@munaemhashmi4481]

​@@FoolishEngineer plz sirr

[@supersilve]

How to calculate the value of a bootstrap capacitor for a given mosfet & frequency?

[@TB-jl9fr]

I = C * dU/dt with I = Q/t, where Q is your Gatecharge and t half of your swtiching period. dU is the slope of the neccessary gate voltage (e.g. from 10V ON to V OFF). Now solve for C and consider a margin of 20% at least.

[@TB-jl9fr]

You can also use the definition of stored energy in capacity. If you know the driving current for your gate you can calculate the neccessary size of your cap.

[@TB-jl9fr]

Or take a look into this application note :) page 5, formula 7 www.onsemi.jp/pub/collateral/an-6076jp.pdf

[@subramaniamss1144]

Add a zener across bootstrap cap, to reduce hv event at vgs

[@aduedc]

Interesting presentation. You did not name a chip for bootstrap IC, just application note. The please add Part # or link to part # datasheet.

[@FoolishEngineer]

Okay

[@MuhammadAjmal-ly3lj]

Sir 6 igbt gate drive circuit diagram Plz

[@FoolishEngineer]

do you have any driver circuit in mind?

[@sumanshetty9438]

Design value for r and c

[@FoolishEngineer]

you can get those values in the driver datasheets

[@lnglng6961]

❤😊

[@alocin110]

what kind of this phucking ic driver is for high side and low side switching? its number.