Open Source boost driver and buck driver

[Giannis_TDM]

Over the last few days, I have been redoing a design I came up with in 2021 as a prototype, with a bit of funding from the styropyro discord this project is now open source!
Dimensions: 10.5 x 20mm
Max Iout: 1.4A typ
Vin: 3-16v
Complience voltage/ Over voltage (output) protection: 8.7v typ
Pictures:

I will be not selling for a year or so due to school but the community needed a boost driver, nowadays almost zero options exist so I give you it.

Zip file containing the PCB project and schematic project (Kicad), Schematic in PDF form and Gerber files to produce the PCB below.
https://www.mediafire.com/file/tlv0dhpu48tmbsi/OpenSourceBoost+v1.0.zip/file

If you want to help me out and fund my endeavours here's my PayPal for donations, every cent helps so please consider donating if you build a few!
https://www.paypal.com/paypalme/GiannisTDM

Terms of use:
1) It is prohibited to mass produce and/or assemble and sell it with an intention for profit, MSRP if sold to members without the capability to assemble/produce one is 10-15$ depending on current part cost.

2) It is prohibited to edit the design and/or publish it under a different name without my permission.

By downloading the files you agree to comply to the 2 terms outlined above.


This project was realized with the help of the following donators:
- Styropyro 25$
-Familial mediterranean diode#6294 15$
-Wild Hiphoser#6976 10$

UPDATE:
The 3A buck has also become open source!!

Zip file containing the PCB project and schematic project (Kicad), Schematic in PDF form and Gerber files to produce the PCB below.
https://www.mediafire.com/file/wgx8t33extx0ci2/OpenSourceBuck+v1.0.zip/file

More info on my website: GiannisLS

 

[Dusty_Lenses]

Bit of an odd chip to use given its limitations.

-max current out 1.4A
-min voltage 4v (boost)


I say this because the popular diodes aside from 405 require much more current, and the min voltage
in is so high. I think a min input V of 2.7v or so would be ideal if such an IC exists.

On a positive note, the layout looks small build friendly

 

[IWLSR5]

Is there anyway to get more amps out of this little guy?

 

[Giannis_TDM]

I don't really agree here, 1.4A is near the max current output I'd recommend for a boost topology due to its inherent inefficiency compared to buck that actually vastly increases with higher currents, also that was a typo that has been now fixed, vin min is 3v.

And with 1.4 you can easily run A140s, sharp 405s and this project's goals were not high currents anyways, it was high compliance voltage so the sharp 488 diodes which at cases need up to 7v and the direct greens with matching vout requirements can be easily run.

also yea one of the other goals was solder ability while keeping a small footprint.

 

[icecruncher]

Personally, I would love to see this produced - at that price. For example, a single battery M140/A140 driver that isn't $25 is nice.

It would be valuable for using all those cheap diode pulls out there that could be put in a small package. Also something that could be recommended to newbs for a simple build with a common diode for very little money. Fits the standard housing and appears to be reliable.

Just my .02

 

[Giannis_TDM]

Personally, I would love to see this produced - at that price. For example, a single battery M140/A140 driver that isn't $25 is nice.

It would be valuable for using all those cheap diode pulls out there that could be put in a small package. Also something that could be recommended to newbs for a simple build with a common diode for very little money. Fits the standard housing and appears to be reliable.

Just my .02

ugh regarding your 2 cents: Single driver pricing with shipping is around 20-25$, Economies of scale do apply here since shipping for even 20 drivers(PCB and parts) is still a flat 6 for components 6 for PCB. For 20 drivers you pay: 8.30 for PCBs including shipping from JLCPCB(granted the lowest spec PCBs but they will do their job.) + 63.57 for components which brings the total to 71.87 for 20 drivers or 3.59$ per driver, without assembly ofc and not including the shunt since you calculate that by yourself depending on your desired current.

 

[icecruncher]

ugh regarding your 2 cents: Single driver pricing with shipping is around 20-25$, Economies of scale do apply here since shipping for even 20 drivers(PCB and parts) is still a flat 6 for components 6 for PCB. For 20 drivers you pay: 8.30 for PCBs including shipping from JLCPCB(granted the lowest spec PCBs but they will do their job.) + 63.57 for components which brings the total to 71.87 for 20 drivers or 3.59$ per driver, without assembly ofc and not including the shunt since you calculate that by yourself depending on your desired current.

I understand

 

[Giannis_TDM]

UPDATE/BUMP:
Renewed the links and added the new 3A buck open source driver, you can find more about it on my website.GiannisLaserShack

 

[nikooo777]

UPDATE/BUMP:
Renewed the links and added the new 3A buck open source driver, you can find more about it on my website.GiannisLaserShack

good stuff and thanks for contributing!
I actually have a question: you mention that "Discharge the output caps with any metallic object across the 2 pins (A and C). Failure to do so will result in permanent damage to the diode and/or driver."

Could one just add a resistor between A and C with a high enough value not to influence the driver during normal operation but to allow for the capacitor to self discharge when not powered?

 

[Giannis_TDM]

good stuff and thanks for contributing!
I actually have a question: you mention that "Discharge the output caps with any metallic object across the 2 pins (A and C). Failure to do so will result in permanent damage to the diode and/or driver."

Could one just add a resistor between A and C with a high enough value not to influence the driver during normal operation but to allow for the capacitor to self discharge when not powered?

Sure, 10k should be fine

 

[Giannis_TDM]

Also I want to point out the capacitor is only a problem when not connected to a diode, the diode parasitics will discharge it anyway.

 

[Giannis_TDM]

Also another note, I measured the leakage with an electrometer and just by the capacitor bank leakage current without a resistor it self discharges in ~1 min to a safe voltage and in 5min completely.

 

[nikooo777]

Hey @Giannis_TDM,
Thanks again for the clarifications above.
I was looking into getting it manufactured, do you have any suggestions? I was considering jlcpcb but I've never ordered a PCB before so I'm not too sure.

if it's not too much to ask, could you let me know what parameters you usually go with?

Do the cutouts actually get cut out or do I have to select the more expensive options such as "panel by jlcpcb"?

I was starting off from the provided gerbers zip.

 

[Giannis_TDM]

Hey @Giannis_TDM,
Thanks again for the clarifications above.
I was looking into getting it manufactured, do you have any suggestions? I was considering jlcpcb but I've never ordered a PCB before so I'm not too sure.

if it's not too much to ask, could you let me know what parameters you usually go with?

Do the cutouts actually get cut out or do I have to select the more expensive options such as "panel by jlcpcb"?

I was starting off from the provided gerbers zip.

0.8mm thickness enig 4 layer for buck, if you want exacly what I use, black silkscreen and TG155 material extra
yes the cutouts do get cut out.