Archive

Archive for July, 2012

MiniPiio DIO16 v0.10

July 24th, 2012 No comments

The third and final board we built from the batch of PCB’s we received on Friday was the MiniPiio_DIO16.

The MiniPiio_DIO16 is a 16-channel digital input/output add-on card for the Raspberry Pi. The board can use either a Microchip MCP23s17 (SPI) or a MCp23017 (I2C) Port Expander IC.

The choice of chip is done by jumper headers on the PCB. In addition the I2C and SPI address is also selectable by jumper headers. Finally, the choice of SPI Chip Select (SPI_CE0 or SPI_CE1) can ne made via a jumper header. By my reckoning thats 7 jumper headers.

The I/O ports from the chis are brought out to two pin strips. As well as I/O each pin strip has a ground, while one has a fused 5V supply and the other a non-fused 3.3V supply.

The schematics are here

Categories: Uncategorized Tags:

MiniPiio ULN2803 v0.10

July 24th, 2012 No comments

The second board we built over the weekend was the MiniPiio_ULN2803. From its name you can guess it’s a printed circuit board with a ULN2803 8-channel Darlington driver. The ULN2803 allows us to drive cicuits with significantly higher current (up to mA) then we could with just the Raspberry Pi GPIO pins alone. The GPIO Pins are connected to ULN2803 inputs, with the its outputs going to an array of strip headers laid out as servo pins.


The board design was done in Design Spark PCB and a PDF for the schematics is here.

Categories: Uncategorized Tags:

MiniPiio ProtoBoard v0.10

July 2nd, 2012 No comments

I’m really pleased with the design of this MiniPiio board.

It fits it’s purpose perfectly. A small 170-pin breadboard you can plug directly onto your Raspberry Pi and have access to the GPIO pins from the RPi’s Expansion Header. You can’t see it but it has the option of a 3.3V voltage regulator to give you more current for the 3.3V for use in your circuit design.

The schematic is here:

Categories: Uncategorized Tags: