I thought about another thing.
I believe that the components are not meant to work in higher currents.
What if we change the Inductor and the Diode to something more quality for example IHLP2525CZER4R7M01 and SBRT15U50SP5-13
I haven’t looked into replacing the components on the LD29. I haven’t measured but I think the LD29 can produce 4A at least without dying. I do not know the efficiency at high drive currents. As you know I’ve been more interested in assembling a driver from parts than modding other drivers. Even though that hasn’t been working out so well
What I would do is strap Pin 5 (PWM) directly to VCC. Then I’d switch Pin 3 (Enable). [unless that didn’t work. Then i’d do it the other way around ] Remember that this gives you no low voltage protection or anything else that the MCU would normally provide.
A tiny10 still takes up a lot of space and requires many air-wires in order to splice it into the stock driver (Vcc, GND, PWM, BAT+). An LD29 driver already wastes a fair amount of space since it must be installed with a contact board. See below for a picture of the first generation adapter boards. They do not work, I became confused when laying them out. I have already ordered replacements. These boards should just reflow in place of the stock PIC and lift the ATtiny up by that much. The whole assembly should remain shorter than the height of the inductor.
EDIT: Here is an Eagle screenshot showing both sides of the board. The ATtiny is on the red (top) layer, the bottom layer sits on the driver board. Pin 1 is marked with an empty white circle.
B.T.W
so without an MCU, this driver can work with a momentary switch connected between pin 3 to vcc and pin8 to vcc ?
I mean while pressed: light is on, otherwise: light is off.
OH MAN! I so like where you are going with that. I've always missed being able to do manual pulsing (e.g. Morse code, etc). I'm gonna add another momentary to my current mod for that. Thank you!
No problem It might be a nice project!
you may also use a reed switch instead of a clicky switch, it might be cooler - that’s what I plan to play with.
I have ordered some more components and LD-29.
I’ll try to make a nice mod when I receive it. H)
I’m going for ‘dropin’. If we had to use jumper wires I’d just stick w/ a tiny10. You do have to file each one down. Once I had the non-functional v04’s in hand I filed down all 4 edges.
Thanks guys. I must have been not in my right mind when I did v04 of the adapter board. Hopefully I’m in my right mind now. I’ve reviewed the board a couple of times and it v06 continues to look right, so I think we’re OK.
Since this PCB does not expose any of the bottom leads to your soldering iron I consider it similar to a MLF package. In my opinion the best way to install these is going to be hot air reflow onto a clean PIC landing pattern. Use desoldering braid to clean up all the old solder, then apply solder past, then reflow the PCB into position.
I was reviewing the pinout just now to do the required STAR firmware modifications and realized that there’s a small problem with the adapter PCB for this application. The offtime cap is on pin 6, which the adapter brings straight through (to pin 6 on the ATtiny13A). Unfortunately there is not an ADC on that pin, it cannot be used for offtime.
Also, it seems that hardware PWM is only available on Pin #’s 5 & 6! Lucky for us #5 is the PWM pin.
For the LD-29 Pin #2 is NC, so hooking the ATtiny up to that pin doesn’t do anything. Instead we’ll move Pin2 on the attiny to the #6 position on the PCB and not worry about losing any features. At this point the board is getting a little crowded:
FW needs mods. I was planning to work on them tonight but haven’t gotten around to it yet. PWM out must change pins, ADC changes are needed for LVP.
Yes, you could just wire up the cap as you described.
I’m not 100% positive that we can easily do the offtime cap & battery monitoring at the same time using the stock setup, but we’ll see once I wade into it. The offtime cap needs to be compared against a lower reference voltage than Vcc, so we normally compare it to the 1.1v internal ref. The battery monitoring voltage divider needs to get compared to Vcc. We’ll see how that pans out! I think it will be OK.
Oops, this is just me being crazy again! Totally insane. The ADC doesn’t return a boolean value (maybe the comparator does?). The code is already fine to do both. Ugh, the things I say sometimes. The only thing we need to tweak is voltage we compare against and all the values.