Carambola IO board with 8 relays and 8 inputs

Time to interface this great Carambola board I have. The I2C board I made up in the last post worked really nicely with the Carambola development board, so this seemed the natural progression.. Piggyback the Carambola on the 8 channel IO board, give it some power, an Ethernet jack, and this should be a nice little board for control / monitoring.  The board can work either wired or wireless, and by using a LM2575 Buck switching regulator, the board can run from 5V to 40V.

Here is first sheet of the schematic:

Schematic for Carambola IO Board with relays (1 of 2)

Schematic for Carambola IO Board with relays (1 of 2)

The second:

Schematic for Carambola IO Board with relays (2 of 2)

Schematic for Carambola IO Board with relays (2 of 2)

All done in KiCad. Below is the PCB layout.  Might have got it onto a single sided PCB with a few links, but pushed the boat and went double sided for this one! The components are all through hole so this should be easy to make when the parts arrive. I’ve designed in a header on the right hand side that would allow a 1-wire DS18B20 to be connected along with breaking out the i2c, SPI and UART. The PCB layout fits neatly on a Eurocard PCB (100 x 160mm).

Two layered PCB for Carambola IO Board with relays

Two layered PCB for Carambola IO Board with relays

All the info you need should be here: Carambola IO Board.tar (KiCad project files, BOM for Farnell parts, etc)