UPDATE II: PCB stuffed and tested.
The chip availability problem has a lot to do with it. We modified the v2go board to use the SSOP version of the PIC24FJ64GA002, which seems to be more widely available.
We normally work with SOIC chips whenever possible. It’s an easy surface mount size for the timid solderer, and it’s an easy size to prototype on homemade PCBs. The SSOP PIC makes sense here, though, because FTDI only makes the 232RL USB chip used on the Bus Pirate in SSOP and QFN packages, we’re using professional PCBs, and the vast majority of these are being made in a factory.
Changes to Bus Pirate V3:
- Changed to SSOP PIC24FJ64GA002-I/SS
- Removed unnecessary pull-down resistor R18. Verified in datasheet that VR3 & VR4 are off when enable pin is open.
- Moved and rotated the CD4066 (IC3) for cleaner routing and (maybe) sufficient clearance to fit a shrouded header.
- Thicker power traces, bigger power vias.
- PCB is thinner and slightly longer, USB jack centered, R19 aligned with other resistors.
- Moved USB LED to top.
- Switched ADC and 3.3V pins.
- Will be programmed with V2+ firmware. Includes a power-on self-test mode triggered by starting with the PGC pin jumpered to +3.3volts. Quality control will be faster and more thorough.
- Code name is v3, may end up being versioned to v2.5 if the firmware is 100% compatible with v2go.
Look for the new PCB in the SVN soon.
Make your change requests in the comments.