The cheapest mosfet anti spark switch build ever, hopefully

From what I understand the inrush to charge the capsitors on the VESC is what blows the anti spark and if I rember right there was a post saying that was over 1kA. Could you not just double up the mosfets to make it more reliable? Put 3 more on the back or some thing? I may be completely wrong and that wouldent work for some electronics reason.

You use an RC timing circuit to limit in rush current.

Or an expensive power resistor precharge network…

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You could potentially just stack fets intil it works.
the real problem is the lack of precharge circuitry

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Flipsky tried to stack 10 MOSFETs glued to a heatsink and it still failed.


wait ;ike actaully? 10 full size fets? thats hilarious.
I suppose its not about the amplitude but the speed of the rising edge


It’s the power dissipated in the pulse surge.

I literally have two open source designs available that both have been tested by members and address this problem. Time for me to make a thread.


Thanks for the info
I was looking at the ltc 7001 a week ago.think I will use this one now as it’s proven, high side switching is best option for sure.

Think I will make a 10 qnty batch pcb of these using the above design if anybody is interested will look nice and have a fuse fitted. At cost no profit.


That’s if you don’t mind gamer?

I’d buy a pair as Guinea pig from you or @Gamer43 if you guys do it.

Will mount it rough : vertically with lots of movements and just some padding to reduce vibrations.

Ok just need permission first from gamer, i have pcb nearly finished will send it off next couple of days I used to be a pcb designer :grinning:.

pcb only, no switches, will be nicly insulated double heat shrink, and have cables and connectors, will have a proper fuse in it, no automotive fuses, which are not rated to 60v DC, but saying that they still probably work, just like to do things properly.

I’m sure it will work perfect as the ic used is perfect for that application

Like I said will be at cost no profit, just making a batch of 10 as I need 2 will ship world wide at cost.

Should be ready in under 2 weeks hopefully as pcb house I use is pretty quick.


What’s wrong with 58V midi fuses?

I’d be in for one or two, let me know cost.

I believe it was explained your switch doesn’t provide an inrush protection? No offense, correct me if I’m wrong.

some automotive fuses only ratd to 42v max, they would probably work ok, but would like to use something with a room for error, so id probably go for a 100v fuse.

I‘m no electric engineer but this looks fine for me on a 12S pack

think i will forget the fuse think most people already have their own

Ok now have permission from the owner of this proven design, if anybody wants one at cost please let me know thanks


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