SparkFun will be closing early at 3:30 Friday 5/27 and remain closed Monday for Memorial Day (5/30). Orders placed after 2pm MT on Friday (5/27) will process and ship out on Tuesday (5/31).


Member Since: May 31, 2006

Country: United States



Hardware/embedded firmware design engineer



  • It is NO. To control 240V, you would need two. If the load doesn’t use the neutral, you could get away with one, but that would be against NEC and a safety hazard as the load would still be live with respect to ground or neutral when turned off. If you are in a country where one side of the 240V is ground-referenced, then you would only need one.

  • Why is one pin cut off from the processor chip? There’s certainly enough space on the board to have included the pad for that pin…

  • It would be nice to have some way of combining the shipping for the hourly discounts. Now, you had to pay shipping once per purchase (ie, once per hour) even if you only wanted one board from that batch of discounts. It wiped out the savings on some of the smaller items.

  • When mounting this board, use nylon screws. The screw heads come way too close to the high voltage traces and could electrify your enclosure.

  • When wiring the GFCI, make sure the neutral wire (normally white or blue) is connected to the silver-colored screw. It looks like it may be backwards in the picture above, and if so, can be unsafe.

  • In your schematic, you have Aref tied high. If the ref mux isn’t set to external reference, you can be drawing some current thru it (worst case, if you set it to internal reference, you are tying the output of the on-chip bandgap to Vcc)

  • Amazing what you can do with an Arduino these days…

  • Since they didn’t mention it, these are tantalum capacitors. The end with the stripe (usually) is the positive side. Also, they must be derated for safety; I wouldn’t use a 16V tantalum above 8-12V

  • The board only uses one of the 5V pins, so that will limit the maximum current on the “5v” side

  • For a real smt challenge, look at http://www.delorie.com/pcb/smd-challenge/

No public wish lists :(