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

This is why I don’t even bother trying to use an iron for smd anymore. Solder paste + hot air is much easier.

Thats how I make those hot air gun and solder paste.

I only occasionally swap resistors or add leds in the 1206, 0805 range. So not very often. Hot air station for me doesn’t make sense cost wise. I’m okay with an iron, but a good magnifying head piece with lights built in might be my next purchase.

If I built drivers, then a hot air station might be worth the expense.

I am trying to get the OTSM drivers to work,

does only get low mode, nothing else

the 2.
gets only low-medium-high
tapping often does not enter config mode
long clicks are not working at all

the 3. only in low mode

I have a helluf a time getting the parts to stay in place with hot air, even slowing the air flow rate way down. Is there a trick I am missing? Maybe I need to mount the board differently and hold the parts in place somehow. But, with a bunch of parts that is not likely to happen…

You could try the skillet method for the side of the board that has the smaller components, and then hot-air the 7135 side.

Which size driver? Which configuration? (1S / etc) Is there a bleeder installed?

Attiny 25V
no bleeder

1S R1 1k / R2 3.3k
2S LDO R1 1.78k/ R2 2.21k

I got the feeling the resistors are maybe switched in manual description R1 smaler than and R2 is opposite to normal Bistro drivers?

build and flashed like in Flintrocks topic
avrdude -c usbasp -p t25 -u -Uflash:w:bistro-TAv1-OTSM-HD-attiny25.hex -U lfuse:w:0xd2:m -U hfuse:w:0xde:m -U efuse:w:0xff:m

avrdude -c usbasp -p t25 -u -Uflash:w:bistro-TAv1-OTSM-LDO-HD-attiny25.hex -U lfuse:w:0xd2:m -U hfuse:w:0xde:m -U efuse:w:0xff:m

the 2S LDO needs a diode which is not present at the 17mm board, so I need to piggyback this

OK adding the diode to the 17mm 2S worked, its now alright

maybe the hex file he delivers is corrupted for 1S

You can try the file I gave you for 1S, but the modes are customized:

battcheck <- turbo <- very low <- STARTS HERE low -> 1x7135 -> all7135s

edit: facts

I figured it out

I made a mistake and populated C1 with 10uF instead of 1uF
used to do always 10uF there for Narsil and TA Bistro drivers

reflowing a 1uF solved the problem

Minor adjustments to OP

added info about NarsilM
Prices reduced slightly for OTSM and LDO due to quantity discount and a cheaper tantal cap with same specs
if you got Bistro HD OTSM message me to get this new OTSM part prices and a paypal refund as the original pricing was too high

as Oshpark was so kind and did more 46mm with correct solder mask I refunded the 2/3 costs on this size

to show the price difference from flintrocks suggested tantal cap to another brand with identical specs
prices does not include 19% import tax

I did some changes for 2S Narsil lights

the shut down voltage should be highter if the cells are not perfectly matched
not going below 3V per cell here

in a 1S light lower is no problem, but 2S needs some buffer

all SIR800 FETs are used now


Great news! Thanks!

Pleasant surprise but if given the choice I’d rather you had kept it and had a :beer: as thanks for the time and work on these drivers. That said, I respect the decision and would do the same in a similar situation. You have my respect and appreciation and I look forward to the possibility of future offerings.

good news Kaidomain delivered 10 short and 10 long 6mm diameter springs today

here a pic, why 15mm Bistro OTSM is a bad idea as the driver has no C2, R1 and R2 pad
R1 and R2 are soldered together with the red wire in the middle and soldered under the Attiny25V to pin4 of the MCU
C2 sits on the indicator LED resistor with cut trace on one end
solder bridge from diode to C2
looks a bit messy as I had also to change C1 from 10 to 1uF

and my 38.5mm Cuoroi LDO piggyback 2S/3P
driver needs to be cleaned from solder paste and flux residue which got there getting it on the LDO legs and C2 soldered

today springs came from Kaidomain, so I soldered them for the people who dont think they can do it, it adds 2.5$ shipping costs and 0.5$ for soldering
on the 17mm driver with long springs its a tight fit

One thing discovered with Bistro OTSM 2S

2S LDO setup does not support LVP as it uses the internal voltage reference compared to MCU voltage
problem is the LDO gives the MCO constant 5V

Have you tried out the lvp on the LDO Narsil M yet? I hope it’s working well.

Btw, on my order I just want the long spring loose. I can solder it on.

so did the Bistro drivers I assembled so far
and the Narsil v1.4

I had 2 drivers where in 2S operation one AMC7135 had this parasitic drain issue when the driver is in sleep mode
they are oficially not build for 8.4V

still waiting on boards from Oshpark that I have ordered later as more were requested than originaly planned

I printed the shiping addresses with information which drivers and export declaration
then used residue tape to fix the drivers where they belong
also wrote on the tape the drivers specs

just amazing that big order from Kawiboy

cant compile NarsilM there are bugs in the firmware Tom E needs to check