7135 driver chips

[DavidEF]

@pilotdog68

Wow… That would make things much easier. I’m going to start doing that now

Yep, I guess I oughta try that myself! I have such a hard time even stacking one on top of another!

[pilotdog68]

My plan is to stack them like that before I even reflow the first one

[michael3]

@djozz

is that 12 7135’s total? and is this the fet / 7135 driver that is used on the blf a6? or is it just one you have done for something else?

[michael3]

In light of our conversation who here of you many modders would want take my m1 convoy and put this kind of driver in it? I am looking to see if anybody would and what the cost of parts and labor
might be? so that would be enough 7135’s to reach 40 to 60% somewhere in there and the fet running 100 % with some type of timer not sure what is best at that output. so the modes would be moonlight(1/2 lumen or so) 5 % ,25% , 50% ( could be 40% could be 60) and then 100 90sec then drop to the med 50%. would the guppy drv work with this or would it have to be modified? thanks

[Rufusbduck]

Probably cheapest just to get one customized by RMM as shipping would be $5.50 or so each way. A few others probably have drivers in hand and coud flash them as well if you had your existing light modded.

[Mike_C]

@DavidEF

@michael3

is there a link to where he has them listed some discussion about it? thank you again,

Yeah, he mentioned it in a couple places, but it’s hard to track down, since it is in other people’s threads. AFAIK, he hasn’t started a thread of his own about it. I did find in the Attiny25/45/85 thread, he had this to say in post #178:

@Mike C

Here is my 85 driver board I got home while I was away. The rather radical changes I made are that I’ve put the OTC, voltage divider and E-switch all on the same pin. The idea is that the voltage divider resistors will be of large enough values so that R2 also acts as a bleed resistor for the OTC, and as the OTC is on the same pin it will be constantly charged by the BAT+ input. Voltage readings should be normal except when the E-switch is pressed. I don’t know if I can get this to work, but I just have to try. Why? Because I want to use my smooth adjustable output level of any amount of AMC7135s on up to 7 on constant current with an additional single AMC7135 for PWM between, and also have a FET for turbo/boost mode. I’m doing this on the 84 and love it, so this is an experiment to see if it can be done on the limited amount of pins that the 85 has.

I actually managed to squeeze in a total of 10 x AMC7135s, but don’t know if it will be too tight to be able to flash the MCU, so I put those two additional ones next to the pins of the MCU so they are the ones to go if it’s too tight with 10.

No spring as I will bridge with stiff copper wire with vias on each end of the MCU, and the MCU needs folded legs. Resistors and caps are 0603 size. Ground tabs on the AMC7135s need to be cut off a little, as does the PSMN3R0-30YLD FET, and made custom Eagle parts for these cut parts. No other way to fit all this stuff on a 17mm board otherwise.

No idea if this will work at all. It’s just an idea I have to try… It is a hobby after all…

Edit: Removed images, new version in the pipeline…

In post #185 of the same thread, he said this:

@Mike C

I’ll be driving 5 outputs. 3 outputs for AMC groups of 1, 2 and 4 for any number of 1 to 7 on in constant current, another output for driving a single AMC7135 with PWM, and the last is for the FET. I do this so I can seamlessly adjust the output from moonlight to all 8 AMCs full on, using PWM with the single AMC to fill in the gap between each constant current AMCs. I did it on my ZY-T08 project and just loved how it worked so now I want to try it on a 17mm driver for a triple XP-L HI light with dual switch setup and a FET for turbo mode.

I haven’t thought about the 85 having PWM on four pins as I only use it on one, except on my dual LED headlight project where I use two (but it uses the 84, not the 85).

I’ll make a driver thread when I get ’em ready. I’ve just tested the first version with the off time cap, voltage divider and E-switch on the same pin, and it works fine using the pin for all three functions. I did however bump into an issue with the reset pin getting voltage from somewhere, turning on the FET constantly no matter what state the pin is in, but I can’t find any shorts with a DMM. I know someone posted info about capacitance when using ground layers, so it might be an issue with that but I’m not really sure. Anyhow, the new design is with more isolation between traces and polygons which should fix capacitance issue if there is one.

I’ve also taken into consideration that someone might want to PWM the FET, so what I’ve done is that I’ve detached the FET from the PB5 pin and given it a solder pad where I can choose to connect it to either PB5 (original design) or PB3 (PWM capable pin). The string of 4 x AMC7135s is also detached, so I can connect PB3 to it, or connect it with the PB2 string which then can be connected with PB1, basically making it a 3 channel driver (1x 7135, 7x7135 and FET) all on PWM capable pins. So PB3 and PB5 from the MCU, and the string of 4 x 7135s and FET, are all not connected to anything and have to be connected to pin of choice by solder pads. To make room for the solder pads I ditched two 7135s so total is 8, but that’s all I want anyway as I want to use my smooth adjustable output method. The added options of choosing which pin to put the FET and 4 x 7135 string on will make the board usable for more people, and also easier to develop as I don’t have to mess with the reset pin. The downside to this is that if you solder pins together (other than PB3 or PB4), then flashing won’t be possible as these pins will be shorted. I’ve looked long and hard for small DIP switches but there does not seem to be switches small enough to fit. They need to be pretty darn small, like max 3mm length and 1mm width per switch if I am to be able to fit them. Anyone know of any, I’m all eyes and ears!

Anyhow, the new design is on the way, but I can still use the current board to continue to port my 84 firmware to this platform… but there is a lot going on at work and traveling so progress is very slow… When I have something to show I’ll make a dedicated thread for it. In the meantime I won’t be very active here for a while.

[DavidEF]

@Mike C

I’ll make a driver thread when I get ’em ready. I’ve just tested the first version with the off time cap, voltage divider and E-switch on the same pin, and it works fine using the pin for all three functions. I did however bump into an issue with the reset pin getting voltage from somewhere, turning on the FET constantly no matter what state the pin is in, but I can’t find any shorts with a DMM. I know someone posted info about capacitance when using ground layers, so it might be an issue with that but I’m not really sure. Anyhow, the new design is with more isolation between traces and polygons which should fix capacitance issue if there is one.

I’ve also taken into consideration that someone might want to PWM the FET, so what I’ve done is that I’ve detached the FET from the PB5 pin and given it a solder pad where I can choose to connect it to either PB5 (original design) or PB3 (PWM capable pin). The string of 4 x AMC7135s is also detached, so I can connect PB3 to it, or connect it with the PB2 string which then can be connected with PB1, basically making it a 3 channel driver (1x 7135, 7x7135 and FET) all on PWM capable pins. So PB3 and PB5 from the MCU, and the string of 4 x 7135s and FET, are all not connected to anything and have to be connected to pin of choice by solder pads. To make room for the solder pads I ditched two 7135s so total is 8, but that’s all I want anyway as I want to use my smooth adjustable output method. The added options of choosing which pin to put the FET and 4 x 7135 string on will make the board usable for more people, and also easier to develop as I don’t have to mess with the reset pin. The downside to this is that if you solder pins together (other than PB3 or PB4), then flashing won’t be possible as these pins will be shorted. I’ve looked long and hard for small DIP switches but there does not seem to be switches small enough to fit. They need to be pretty darn small, like max 3mm length and 1mm width per switch if I am to be able to fit them. Anyone know of any, I’m all eyes and ears!

Anyhow, the new design is on the way, but I can still use the current board to continue to port my 84 firmware to this platform… but there is a lot going on at work and traveling so progress is very slow… When I have something to show I’ll make a dedicated thread for it. In the meantime I won’t be very active here for a while.

Looks like your driver will be VERY useful to a lot of people! The amount of flexibility you’re incorporating into the board design is outstanding! I’m looking forward to seeing your driver thread when you’re done!