[WIP][mostly retired] 17mm DD+7135 -- linear regulated driver w/ FET turbo

I just sat down and read through some of these revisions and wow! Pretty sure it’s just me…

Oh, also I don’t think Werner made it clear but that momentary firmware could also be used for one-shot programming of ATtiny13A’s with our normal USBASP programmer. If you know your modes configuration it seems to me that Werner’s firmware is good to go… you just can’t reprogram.

I probably make it sound more complex than it really is. There’s really nothing super complicated about it the design, it just turns different quantities of 7135 on and off, plus has an FET to turn on and off.

Hi guys, excellent work as usual! :slight_smile: Im just wondering wouldn’t that be excellent driver for one XM-L2 if we put 8 7135’s and use Attiny13a to control it like 1x7135, 1+3x7135 and 1+3+4x7135, so then we have quite nice efficiency on all modes right? Maybe this 1x7135 should go with PWM if possible. Next we need someone who can draw this driver to Oshphark and little more code. No need for FET, we could stack 7135’s if more power needed right? What do you think?

Thanks!

Stacked 7135’s can’t do what the FET can.

Also, this driver is on OSH Park.

Maybe after the firmware is solid for this one I will make an 8x7135 driver with no FET.

Pilotpptk once made this but it got never released…

There is a very easy to build fuse resetter that I have tested it works. www.simpleavr.com/avr/hvsp-fuse-resetter

I look forward to a day when this has established firmware…

I took this guys version and cut it down smaller, only need the adapter board for the ATtiny13
http://mdiy.pl/atmega-fusebit-doctor-hvpp/?lang=en

Atmega fusebit doctor (HVPP+HVSP) Short board Warhawk’s tweak

adapter_HVSP WarHawk’s tweak

Can cut everything off above DA7 for even smaller board

I think on the guys later revisions, he fixed the problem with one of the traces on his board that got cut by a drill (this is his unmodified full size board [other than me tweaking and filling the polygon pours between traces], look at the very bottom in the center, the power trace runs right thru a drill hit) [I did mention it to him in his thread, I think he fixed it, but my tweak I re-routed it for the “short board”]

Could we just drop one of the groups of 7135 chips? That would make things quite a bit easier… Only four pins are freely assignable without consequence, and the driver tries to do I/O for at least five independent components.

So, it would then have:

  • PWM1 = FET
  • PWM2 = 1x7135
  • I/O A = Nx7135
  • I/O B = off-time cap or e-switch

And no need for any new flashing hardware.

Adding a PWM-controllable 7135 chip to a FET driver is a huge upgrade which addresses most of the shortcomings of a FET. Adding a second set of 7135 chips, minus the PWM, helps make a medium mode more efficient but otherwise has limited usefulness. A third set has even more diminishing returns, and comes at a pretty high cost (either requires overlapping pin functions and harder flashing, or requires dropping the off-time/switch pin).

Personally, I’d drop the second set of 7135 chips too, and make room for another sensor or something. One FET, one 7135, and two pins assignable for switch, off-time cap, or thermometer.

I don’t see big problems with the fuse resetting. If once a working firmware is available we just need to flash it once. I seldom change my firmware, I also never use the stars, I just make it like I want it to be and voila…

My arduino nano board arrived today, I will try to add a transistor and some resistors in the next days…a nano costs less than 4$.
I will try this:
http://homepage.hispeed.ch/peterfleury/avr-hvsp-fuse-restore.html
—-
Warhawk a PCB for fuse resetting is cool, it looks a bit big. How are the dimensions?

Adding a wire to my soic clip and using a “fake ISP” socket to reset the fuses, seems to be the best way for resetting assembled drivers, I hope that works because there is 12V on the reset pin!!!

Freely assignable without consequence: you mean 5 pins, not 4? 8-3=5, or am I ignoring something again? You were referring to the pins that are left after we establish a voltage monitoring pin.

As far as the groups… I’d say the FET and the first 7135 get you repeatable Moon mode with PWM and maybe a small Low without PWM. The second set gets you up to a total of 2.28A for your regular usage mode, PWM free - so no buzz. With 6 spaces and the option for .35 or .38A components you’ve got a pretty granular ability to setup Medium/High for PWM free operation. With this 7135+FET driver I do agree that any extra sets of 7135 beyond set 1 and 2 are gravy; eg the driver should work acceptably without 4 outputs.

Note that v026 is posted above in post #63 and allows for the FET + 1*7135 + 1-to-5*7135 setup, allowing you to stop using Pin1 and still use all 6 placements if desired. If a temp sensor is desired Pin1 can be fused for use and setup as an ADC. [EDIT: and in that case you’d cut the trace and solder the temp sensor lead directly to Pin1, which is fine because you’d have to remove the MCU from the PCB for any changes anyway since it would require HVSP.]

I agree with the rest, but I don’t think HVSP is intended for in-circuit programming. If Pin1 is attached to Vdd on a 7135 then HVSP will take the 7135 out of spec: there will be 12v on Vdd and 0v on GND, I expect the 7135 to fry.

Since an FET is the least efficient on pwm why not have two sets of pwm 7135’s and the FET fixed (on or off only) and just use it for turbo. With 6 x 7135 that would give up to 2A on pwm and a genuine jump to turbo.

I like that, and the FET can probably take 12v on gate too IIRC (so maybe in-circuit HVSP?), but that prevents smooth turbo ramp down.

The issue is with using non-vector text, what “vector” is is text that each point / line corresponds to an exact coordinate so it will always be rendered / printed EXACTLY as it appears on the screen. Trying to use proportional text you will end up with the text slightly different, either shifted or miss-alligned or even contorted out of shape. I ALWAYS use vector. To many time’s I had boards that came with the text moved half way off the board or moved up to a copper area (and thus not printed at all) or some other way messed up, not once since switching to vector (and also centering it on the point) have I had a render / printing issue.

I cant tell on my phone screen, its to small, maybe it is but if not you really should use vector text.

I use vector text so that I can control the stroke thickness.

The issue was just that I was mistaken. I checked my BRD and Gerber files and the OSH Park render and simply became confused. The text is rotated incorrectly, I will correct this in the next version.

there is only one way to find out I what happens if you power a 7135 with 12V…

I looked in the data sheets I have and some rate it for 10V max on Vdd, so with a bit tolerance and good luck it will work. Or you have to add a jumper pad to the circuit which needs to be bridged to power the 7135 on the resetpin…or I just cut the trace and bridge it afterwards.
I will try to build a resetter and test it in circuit in near future.

I have thought again about removing the tiny for resetting and with a hot air this is a breeze, so a fuse resetter with a smd pad for a tiny could work like the one Warhawks has in mind. Just desolder it press it on the pcb with a finger and voila…

The Atmega fusebit doctor (HVPP+HVSP) Short board Warhawk’s tweak
2 layer board of 2.10x1.79 inches (53.34x45.52 mm)
cost $18.80 per set of three.

The adapter_HVSP WarHawk’s tweak
2 layer board of 1.53x2.10 inches (38.76x53.34 mm).
cost $16.00 per set of three

I don’t have em shared, or have tested them either

Question, is the Teensy an Arduino compatible unit…they are $17 from OSHPark I believe
https://www.pjrc.com/teensy/teensy31.html

Interesting Why Teensy is Better Than Arduino-TechnoGumbo

I don’t think that’s the question. :wink: Not when we are picking up Arduino clones for <$5.

Interest has been expressed in not using Pin1 (Reset). There are not a lot of different pin configurations which make any kind of sense. Here’s what’s on my mind, please let me know if I’m missing something:

Pin 1 (Reset)

Pin 3 (on/off)

Pin 5 (PWM)

Pin 6 (PWM)

v029 trace config

Current/Original

3*7135

2*7135

FET

1*7135

c+a

alt Current (v026)

n/c

5*7135

FET

1*7135

a

proposed

n/c

FET

5*7135

1*7135

b

proposed

n/c

?

?

?

?

If anyone thinks it’s worth messing with for testing, I’ve devised a PCB which requires trace cutting before use but allows all 3 configurations (as a one-time setup option). I absolutely do not think that this is a great idea for most people building their own boards, as it is too confusing and trace-cutting in this location is basically one-way. This is really just intended as a semi-flexible test platform. Note that “c” is on the bottom and requires both cutting and a solder jumper. EDIT: “a”, “b”, and “c” all indicate CUTS which must be performed.

Wight, has low-voltage protection been designed into this driver?