I wouldnāt write it off, Iāve got a project Iām in the midst of right now running the entire driver at the tail of the light off a capacitor bank charged up through the bleed resistor(s).
If I can run an entire driver off caps I would think someone could run just a FET, and just full-on/off in the same manor.
50ohms of resistance at the head (needs to be rated 1w or using a bank of 1/4 or even 1/10 Watters) and ~350uF at the tail has been working on the breadboard without issue. Time will tell when I switch to a real PCB with smaller package caps but folomov did it so Iām betting I can too.
I bring this up here cause like I said, I donāt think it should be impossible or even difficult at all to run the switch FET without a battery, just need to do a lil backyard EEāing.
Oh also lumintop does it in the Ti Tool AAA (but their implementation isnāt all that great TBH)
So, Iāve finally decided to make about 10 of these FET switches.
Iāve finally understood of how this works, but one thing is still unclear to me:
Is it possible to use a super capacitor with a very high value resistor to prevent overcharging to the cap?
Itās the only component that Iām unsure if I should actually order.
According to post 24 it is being charged to 3.3 volts and the charging is limited with a 2.2k resistor in series with a diode, looks like changing
the charging rate is pretty easy.
The spec sheet for the battery says it has ācontinued stable capacity characteristics even after the battery is overdischarged down to 0.0V. ā
So maybe its possible to drain the battery to keep it from shorting out and destroying itself while its being installed.
If your going for the lighted indicator fet switch then rev.B has a lot lower quiescent current. I think loneoceans also added a second fet pad in the middle of the spring in rev.B. Are you building fet switch with the indicator or just the fet switch?
If shiczobovineās design uses the same components, I would just order both, 3 of each and wait to see which one works better. Then order more of the design you like. Seems like people are having problems getting the battery installed and your going for the super capacitor. Seems experimental.
You can use either one. He describes it back in his first post under the 16mm oshpark link. Itās also in the descripition at oshpark.
If you are using the LFPAK33 that is.
Let us know how it goes Blue. Iām going to wait and see how yourās goes before I order any. I like the super capacitor idea.
Iām pretty sure you already know about Arrowās free shipping. I order everything I can from them. Thought I mention it anyway.