Dumb question, "stacking" current sense resistors... literal?

Like, just on top of the other one? A literal stack? To put current sense resistors in parallel I mean. Is this just a phrase? Or is it cool to literally stack them? Sorry, dumb question. I feel like it’s literal but it sounds so silly, had to check lol

Also, any good AliExpress stores for these? Or you just go with mouser/digikey

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It’s what it means yeah, the power dissipation is probably not great for the top one, and it probably adds a bit of resistance to the top one. If you find the right value then just replace it. Paralleling allows to make odd values.

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Yes, you literally stack them in parallel to reduce the resistance:

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Thanks guys! I made exactly that one in the picture lol. Put another 20mohm on top. It feels so silly I had to ask.

It brought tailcap amps on 35% from 2a to 3.8a, and 100% from 5.5a to >8.5a, so great success!

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A word of caution on doing a Sense Resistor Mod on Convoy Drivers.
Thermal step down doesn’t go below 35% so depending on your host 35% may cause the light to overheat.

Naw, it’s an S2 so it WILL overheat :grin:

Btw, what do you guys think the weakest link is on the driver itself with the sense resistors like this? Like if you had to guess what was going to fail first.

In normal short bursts of use I mean, assuming I don’t let it run for 3 minutes and it all just melts lol

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I have 10 or more S2+ with the exact same sense resistor mod, so far so good!

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Are there ~40w capable emitters in all of those? Or do you do it for some other reason, like brighter low modes or is there an efficiency gain?

Most of them are triples.
For the single SST40 and single SFT40 I stacked a R050 on top of the R020 to get around 7A.