Quality anti spark switch, at cost no profit using inrush limiter


offering this anti spark switch designed gamer43 who has kindly donated design, switch offered at cost no profit involved.
going to do a batch of 10, if enough interest will run a batch of 20 if anybody wants one, purly at cost value no profit involved, as i need two myself nice small pcb.

After lots of research found lots of bad and quite good designs of antispark switches i believe this is probably one of the best ones out there that works uses the Ltc 7004 icinrush-limiter [here] switching the high side which looks after the mosphets, it draws no current when switched off so battery wont drain, included will be a quality switch.
please put your name down if interested. will get prices in the next couple of days but should be in the region of about £15.00, excluding postage.

fuse wont be included, to keep cost of board down, board will be insulated with a double layer of heatshrink will look like this, with switch below will be good for 100 amps, suggest you use whatever fuse you require.

using this switch


I’m down for one but pending shipping haha :stuck_out_tongue:

@b264 Brian have you scrutinized this design please?


There is no design here. We’d need a schematic – or at a minimum a high-res photo of the PCB on both sides without heatshrink on it – to know what this circuit is doing.

I believe this one’s pcb-free, wired point to point. @jonisingt35r you’re in the UK?

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circuit diagram
yes in uk


So there is no precharge stage – this is just an inrush-limiter circuit.

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With a pair of IPB014N06N, or 10x NTMFS5C628NL, it’ll handle upto 6,000uF at 50V without an issue.
I would know because I do this everytime I switch my mountainboard on.

If the MOSFETs still popcorns then increase the size of the capacitor from 100nF to 220 or 330nF.


I’d also like a shipping estimate, Florida 33907

Ok just put your name down so i know numbers

Put my name on the list please.

Ok got 5 people wanting one now, if it reaches 10 by the end of the week will send off for 20 pcbs.

6th send one my way :smiley:

Hello gamer shall i just add larger c for better realibility?
Also, do you get any heat issues what sort of current does your pull?

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Ok, been looking at postage costs to the states so far is 10 pounds, but hope to get this cheaper will keep looking for cheaper options.

Alternatively, you can ship it all to one person and then that person can take care of shipping for the states. It’s more work but it’ll be cheaper for the end users depending on how many people purchase.

i was vthinking of that

The picture is not of this switch he is making… Also, this will draw current as it has always on LDO

EDIT: sorry regarding picture didn’t read correctly but still it is not what it will look like.


Datasheet specifies maximum quiescent current of 400uA at 48V Vin.

Ltc7004 draws 50uA when regulating from Vin.

I will be homest, probably could have rewired the switch to cut power to the logic stage, but I don’t want to overload the chargepump on start up.

oof not LTC will be eating power…