Hi,
I made some progress on the "easy pdk prog" programmer.
Based an the suggestions from you I added the transistor solution to shift the logic output voltage of the STM32.
I also created a PCB and sent the Gerber production files to JLPCB. They will manufacture 10 pcs for USD 2.00
All the parts can be ordered from LCSC so I was able to combine this 2 orders which usually reduces shipping cost.
But I also got a discount for first time order which eliminated shipping cost at all.
The PCB only uses one side for components for better assembly but the size is still very small: 58mm x 22mm (slightly larger than arduino nano).
Features:
- USB powered device (no extra power supply)
- variable and monitored IC VPP (0-15V) to support all models (OTP and flash)
- variable and monitored IC VDD (0-6V) for calibration of Padauk IC
- output voltage level shift to support communication with any IC VDD (up to 6 V)
- extra 8 MHz oscillator for calibration of Padauk IC
- 3 user LED to show status
- 1 button to start operations from programmer directly
Price for PCB + components is also very attractive (depends on how many pcs. you want to make):
1 pcs: PCB: $ 2.00 , BOM: $ 2.39 => $ 4.39
10 pcs: PCB: $ 2.00 , BOM: $ 19.78 => $ 2.19 / pcs
Now need to wait 9-14 days for the stuff to arrive.
JS
BTW: The only thing I miss in EasyEDA is the feature to show components on the 3D rendering of the PCB. Everything else was easy to learn and very intuitive. Great job from them.