I'm trying to use a nice one-button On|Off latching setup on ATtiny85. See for details the last one of these four: http://www.technoblogy.com/show?VOO In a low-power set-up on my breadboard this is no problem; works like a charm and allows for any delayed auto-off.
However, I want to use this for powering up/down my 400W Ebike.
My question is: how to boost the signal from ATties peak 40mA to an acceptable current that can switch a FET or a relay?
I considered diverse alternatives like transistors or 555 based latching schematics, but choose this one since I have an ATtiny on board already. I have zero experience with FETs or MOSFETs, and I'm stuck.
In this thread (avrFreaks, post #6) a BS170 is mentioned, but I cannot simulate the right circuit and I do not understand yet fully what's going on in that MOSFET.
I have considered using a relay, but these are hard to find in an acceptable price range with specs needed (small footprint, shockproof and allowing to switch 10A at 42V). So I think MOSFET is the way to go.
A detail from the schematic of the on/off wiring:
PB0 is set high when system is powered up and needs to switch the 42V. Plz feel free to make any changes on the isolated (simplified) part of the schematic on EasyEDA: Go to schematic
Any help will be highly appreciated!