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QDrives , 11-12-2024, 09:20 PM

Perhaps he wants to run it in liquid nitrogen?

Sniper2 , 11-12-2024, 09:25 PM

i would recommend liquid Helium

QDrives , 11-12-2024, 09:45 PM

Nah, then silicon does not conduct that well.
With liquid nitrogen it is nothing better...

Sniper2 , 11-12-2024, 09:52 PM

colder then nitrogen

Sniper2 , 11-12-2024, 09:52 PM

and it leacks into materials for extra cooling

Sniper2 , 11-12-2024, 09:52 PM

@QDrives

QDrives , 11-12-2024, 10:03 PM

Unfortunately, this one does not give a simple answer: https://nanohub.org/courses/PSF/fall2018/asset/29224
Besides, both will be out of specs compared to the datasheet.

Sniper2 , 11-12-2024, 10:12 PM

wildly

Sniper2 , 11-12-2024, 10:13 PM

OP needs a mosfet module or simply a array

Sniper2 , 11-12-2024, 10:14 PM

that way OP can only use 1

Sniper2 , 11-12-2024, 10:16 PM

@Peg https://eu.mouser.com/ProductDetail/IXYS/IXFN420N10T?qs=6UKyFUzHTlk7jbj%252BcHMbcg%3D%3D

Sniper2 , 11-12-2024, 10:18 PM

u still need to disipate like 200W

Sniper2 , 11-12-2024, 10:18 PM

but now it is WAY more manageble

Sniper2 , 11-12-2024, 10:20 PM

still massive heatsink but something realistinc at least

Sniper2 , 11-12-2024, 10:21 PM

use 2-3 in paralel maybe

Sniper2 , 11-12-2024, 10:21 PM

never used something like this but they make them for stuff like this

QDrives , 11-13-2024, 09:37 PM

@Sniper2 There is no low low ohmic module??? I see with mouser the best is 2.3mOhm for a 100...200V module.
Anyway, the datasheet of the gatedriver also shows multiple FETs.
For the cost you can place about 5 FETs --> 0.2mOhm.
Give that enough board space and you just may not even need a heat sink (in theory!).
However, with the slow turn-on and turn-off, he needs to be careful of the SOA.

QDrives , 11-13-2024, 09:42 PM

And do not forget trace resistance!
A 50mm wide track of 70um outer layer will increase 66°C with 120A.

Sniper2 , 11-13-2024, 09:44 PM

@QDrives i would not call this thing a PCB but a chasis mounted build

Sniper2 , 11-13-2024, 09:44 PM

yes a gate driver PCB may be neded realisticaly

Sniper2 , 11-13-2024, 09:44 PM

10A gate driver unironically may be needed

Sniper2 , 11-13-2024, 09:45 PM

at that current i am not even sure if there are chips

Sniper2 , 11-13-2024, 09:45 PM

let me invent the gate driver for the gate driver

Sniper2 , 11-13-2024, 09:46 PM

like u saud a mounting board could be enough to keep stuff cool

Sniper2 , 11-13-2024, 09:46 PM

but this is like an order of magnitude more then the largest current i did bandle 20A ish thrugh a PCB

Sniper2 , 11-13-2024, 09:50 PM

u also must make sure that all start at the same time and ahve similar Rdson

Sniper2 , 11-13-2024, 09:51 PM

anyway just driving the FETs is a interesting project itself

Sniper2 , 11-13-2024, 09:52 PM

@Peg WHY do u need to switch this current anyway ?

QDrives , 11-13-2024, 09:53 PM

Well, it is not a motor driver or power supply, but the protection for batteries. So that does not switch fast/often.
However, when it switches, you still want it to be reliable, both on and off.
Switch off with 1A of the gate driver, ~200nC gate charge, 5 FETs --> more than 1us to turn off.
However, sourcing is less specified, 300mA max. Lets go for 250mA, --> so it is takes at least 4us to turn on.

Sniper2 , 11-13-2024, 09:54 PM

those times are still reasonable

Sniper2 , 11-13-2024, 09:55 PM

it is ok acording to SOA even at full load

Sniper2 , 11-13-2024, 09:56 PM

then again i would add a heatsink since at start it could get hot fast

QDrives , 11-13-2024, 09:56 PM

Or a fan to cool the PCB too.

Sniper2 , 11-13-2024, 09:59 PM

i like passive stuff

Sniper2 , 11-13-2024, 09:59 PM

reliable

Sniper2 , 11-13-2024, 10:00 PM

u said 5 of those so like 125$ + maybe a 25$ fast driver board with MCU

Sniper2 , 11-13-2024, 10:00 PM

not so bad

Sniper2 , 11-13-2024, 10:00 PM

expensive part is the cable bussbar that comes in and out

Sniper2 , 11-13-2024, 10:04 PM

@QDrives

Sniper2 , 11-13-2024, 10:04 PM

what do u think?

Sniper2 , 11-13-2024, 10:04 PM

is this surprisingly cheap?

QDrives , 11-13-2024, 10:28 PM

I meant 5 of the original mentioned FETs. https://www.infineon.com/dgdl/Infineon-IAUT300N08S5N011-DataSheet-v01_02-EN.pdf?fileId=5546d46277921c32017795d395544683
With Mouser €5 vs €26 for s single piece.

QDrives , 11-13-2024, 10:30 PM

With these currents, everything is expensive if you are not used to it.

Sniper2 , 11-14-2024, 04:28 PM

can work

Sniper2 , 11-14-2024, 04:28 PM

heavy Cu can do wanders

QDrives , 11-14-2024, 08:28 PM

Still a lot of losses in copper.

Peg , 11-15-2024, 09:58 AM

Hi many thanks for the discussion; this is for battery protection system and charging

Peg , 11-15-2024, 10:00 AM

I discussed this item with support team of infinen
I can do the pcb with 4 layers and passive cooling still need to be checked

Sniper2 , 11-15-2024, 03:03 PM

How thick of a copper ? @Peg

QDrives , 11-15-2024, 07:46 PM

50mm wide trace on 140um (4oz) copper is still 38°C temperature rise.