EEVblog #1144 - Padauk Programmer Reverse Engineering

[bitwelder]

Wow, 6 years since the video and first post and Padauk is apparently still going strong. 
Has the product family being updated?

[MOSTAFA IL IDRISSI]

Hello

No one can help me?
Which is the actual version? Where can I find it? On github is only 1.3 Where can I find an actual .dfu firmware?

Hello
I did had the same message as you but finally I get it functionning. in Windows I downloaded this folder EASYPDKPROG_WIN_20200713_1.3 from https://github.com/free-pdk/easy-pdk-programmer-software/releases/tag/1.3 , and then made sure that all compilation and upload are done in CMD inside the folder containing easypdkprog.exe.
I bought some chips in Apr 2025 and the programmer is still functionning
regards

[spth]

Has the product family being updated?

Yes. See the news section on their website (https://www.padauk.com.tw/en/news/). It is mostly datasheet updates, but each time the version of the datasheet is v0.00, that is a new device.

[tim_]

LCSC got a lot of new Padauk Microcontrollers:

https://www.lcsc.com/category/941.html?brand=1246

PML100B (OTP) for $0.0276: https://www.lcsc.com/product-detail/C49173943.html
PFS123B (Flash) for $0.0433: https://www.lcsc.com/product-detail/C49173944.html

They also have the PFC460 in stock now, with 4 FPPAs: https://www.lcsc.com/product-detail/C22365212.html

[tim_]

The PML100B are actually quite interesting. They are capable of driving LEDs at >200mA on three pins. I am suspecting that they are being used in all the low-cost battery powered lights.

PFS123B is a bit more powerful than the earlier flash devices. And it supports a 5V low voltage programming mode - maybe it is possible to program it directly with an arduino or other 5V MCU?

[tim_]

It's possible to configure the driving capability of the high current pins. That way you can even get rid of any external resistors. That's truely low cost engineering.

The pin-out and functionality exactly fits to one battery operated light I have analyzed.

[tim_]

I did some experiments towards a CH32V003 based programmer. This comes at a BOM of <$0.50...

https://github.com/cpldcpu/Splinter/tree/master

[crasheg]

Greetings.
Thank you for the interesting forum thread; you've done a great job!
Has anyone encountered errors with the original PADAUK 5S-P-003 programmer during development?
When using in-circuit programming (I select On-board programming when compiling the project), I get the "IC not working" error. What could be causing this? In my humble opinion, this could be due to the high capacitance on the VDD pin. Is it possible to modify the original programmer for use with the PMS171B given the high capacitance on the power supply line (470uF)?

[crasheg]

Previously, I installed a Schottky diode directly before the PMS171B and programming went without problems, but now I want to get rid of it by modifying the programmer.

[spth]

I printed it with a very fine resolution (0.2mm nozzle, 0.1mm layer height) so it  took a bit longer than needed, however your can print this in less than 30 minutes.

Here the stats:
Build time: 1 hours 43 minutes
Filament length: 2200.6 mm
Plastic weight: 6.62 g (0.01 lb)
Material cost: 0.30 USD

(3D printer used from our local hacker space, Filament used PET-G, not this rubbish ABS).

I've looked into printing some cases using a Sovol Zero using PETG through the standard 0.4mm nozzle in 16min. I had to experiment with support settings a bit to get a good balance between sufficient support, and too-hard-to-remove support. The cases turned out okayish, though naturally not as nice as yours.
I wonder if we should modify the design a little bit to make it work better for the common 0.4mm nozzles. Looking at the 1.2 pcb, there should at least be enough space to make that round column a bit bigger.