Introduction
This page contains the (relatively unchanging) information about v0.1 of the SARduino644 board.
- SARduino644 v0.1
Design Files
| REVISION | DESIGN FILES | SCHEMATIC | PCB | GERBERS |
|---|---|---|---|---|
| SARduino644 v0.1 | everything (.zip) | .sch .png | .brd .png | .zip |
Bill of Materials
Stan Hall sent in a Mouser BOM of all the parts listed below, for easy ordering.
| DESIGNATOR | VALUE | PURPOSE |
|---|---|---|
| IC1 | ATmega644P | Microcontroller (or ATmega1284P) |
| R1 | 10K ohm | Pullup resistor for RESET switch |
| Y1 | 16MHz Crystal | Oscillator (or 16MHz Ceramic Resonator, omit C1,C2) |
| C1,C2 | 18-30pF Cap | Capacitors for Crystal (match required value) |
| C4,C5 | 0.1uF Cap | Bypass capacitors for MCU, consider putting right at 5V/GND and A+/GND pins instead of labeled positions |
| JP10 | 1×6 header | 6-pin FTDI cable programming connection (optional) |
| SV1 | Reset button | 6mm x 6mm tactile momentary switch |
| JP6 | 1×3 header | 3-pin power selector (external or USB) |
| ICSP | 2×3 shrouded header | Standard AVR ICSP header |
| SW1 | Reset button | 6mm x 6mm tactile momentary switch |
| EXTERNAL POWER SUPPLY OPTION: | ||
| D1 | 1N400X | Input protection diode (e.g., 1N4001 or 1N4004) |
| J? | 2.1mm jack | External Power Jack |
| VR-TOP | 7805 | 5V Regulator (any IN-GND-OUT should work, or 3V3 if you want that) |
| C6,C7 | 10uF-100uF | Power Supply Filter Caps |
Errata
- The reference designators are all jacked up on this one.
- Most passives are not labeled by value on the PCB.
- It would be really handy to have more prototyping area in the spare space, it’s kind of hard to do simple stuff with the 644 pins otherwise.
- There is no cap on the reset line from the FTDI to support auto-reset.
- Some extra power and ground rails would be nice for prototyping.
- It would also be nice to have a pad for raw external VIN, in case we’re not using a 2.1mm jack.
- C4 and C5 are really bypass caps for the microcontroller, and should be as close to the VCC pins as possible. Omit from marked placement, and instead put right across power/ground pins on each side of the microcontroller.
Great job. I am about to order one of these from the Free PCB drawer at Dangerous Prototypes. I am not experienced at part selection as my skill level is maxed out building kits. Is it possible for you to provide a list of specific parts from Mouser or Digi-key? Or at least review my part order before I finalize it.
Thanks!