I have a new project for circuit and PCB design. It uses an STM32 MCU (exact model to be decided with freelancer) with several interfaces to connectors:
- I2C interface to DAC chip on the board with some complexity behind it (I have schematic design, but good to be checked upon copying)
- 10 PWM pins connected to timers, 2 x ULN2003 for 8 of the outputs, 2 transistors for the others
- 5 ADC inputs (8 bit), possible amplifier in one of the channels, rest is direct connection to header
- 51 GPIO pins, that include 39 pins directly wired to headers, 5 pins for green LEDs, also directly to headers, 6 pins for programming through ST link/v2 (SWD), 1-2 input pins for mode selection
- Depending on the chosen MCU, if available 2 additional ADC pins and a few additional GPIO/timer pins to connectors
The project is based on already produced PCB, but now I need to increase a little bit the size of the PCB, also some MCU pins are messed up and many components are being removed so there should be no problem with the space. Because of the simplification, probably smaller MCU can be used. I can provide schematic and PCB design files from the previous project to be used to some extent.
I see the following milestones:
1. Schematic design. It will be relatively simple, the previous schematic can be used as a base with multiple components removed, only the I2C connection is new. Because of the MCU pins mess up and probable change to smaller MCU I expect there will be some work around the MCU pinouts. I prefer to make the discussions on the schematic in PDF format during this milestone.
2. PCB design. While I will provide the old PCB, as I mentioned the new one will be slightly longer, but there will be no change in the connectors/mounting holes position. It is a 2 sided PCB. Possibly full redesign and rerouting will happen here so old design will not be of much help. There are some limitations for the component position.
3. Created project for Atollic truestudio for stm32 with assigned MCU pins and necessary libraries so I can start integrating my software and debugging.
4. Final receive of all source files (Schematic, PCB design, Gerber files, BOM, truestudio project, PDF file with print of the schematic and both PCB sides)
Thank you for considering my project!