making 3. Batch Texas Avenger "TA" / Bistro HD OTSM drivers fully tested running Bistro or Narsil, Clicky or E-switch, SIR800

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ordering from Digikey tomorrow

I’m a bit lost with HD OTSM, I haven’t spotted its existence until now.
Reading / skimming quickly through its topic I guess that’s what I want, but is there a summary of hardware differences somewhere?

I’ll take 1 short spring.

Hi there,
Id like to get in on the fun. Intersted in a narsil driver for Convoy L6

My line on the spread sheet looks good.

Question for all (not just Lexel). I have ordered a 46mm for a Q8. I requested the temp sensor set to 60°C. I see on the spread sheet the other 46mm orders have selected 70°C. Am I being too conservative (setting too low)? What would you use for a Q8?

You will have to choose between having low voltage protection and no temperature stepdown (narsil v1.2) or

temperature stepdown, but no LVP (narsil v1.4).

I went with LVP and let my hand control the temperature.

Forgive me my noobish question, but what output does this driver give? Is it able to light up an XHP 70 in an 18650 form? If so, i am interested

It’s a FET driver, so whatever the batteries can give.

In my L6 with Liitokalas it pulls 12 amps. If I put some good unprotected 18650 cells in my same light I doubt it would deliver the same amps just because the voltage will sag more under load. I’d guess 10 to 11 amps maybe.

Is that what you were asking?

Exactly Jason!
So basically, if i use 2S you can light up emitters up to 8,4V and lots of current up to a level where the cells or other parts limit the output?

Yeah, pretty much.

So I made some minor changes to the Bistro OTC board using a high quality 0805 capacitor with low temperature shift and only 5% tolerance this should get better than the standard X7R 0603 one when the light gets hot

also on ordering the parts I looked around and checked if there is a better 47uF tantal capacitor and I found that Flintrock pretty much choose the most expensive on market, getting another brand with identical specifications drop the price by 1$
as I got also over 10 of those capacitors price dropped also

the question is if I can use this new capacitor and save almost 1.5$ to the first Bistro OTSM material calculation, getting you a partial refund on the paypal transaction?

Not sure if it applies to me but no need for me anyway.

OK, I educated myself on Bistro-HD OTSM. Definitely looks like the thing, but I need a clarification. The firmware’s thread mentions that it needs ATtiny85 revision C. It reports that all trial to find it failed. Did you manage to find it?

Bistro HD OTSM runs on Attiny 25V

extra parts price for HD OTSM dropped to 1.5$ as I did change the capacitor brand with same specifications and are above 10 parts Digikey lower prices as well
0.92$ vs original calculation of 2.23$ for the capacitor

Any chance for 45V?

for 0.5$ more I can order 45V I am ordering later today

So I’d like both divers with 45V. Thank you.

Excuse my ignorance but what is the ‘45V’?

Attiny45V microcontroller. It has more memory, which leaves more space for me to do firmware customisation. Unless you intend to change firmware, it’s useless for you.

Attiny 45V more memory than the 25V
V is some sort of low voltage enhanced version that is needed for OTSM to work

Thanks for that information. I won’t likely be changing the firmware so not for me.