New PCB batch

November 25, 2012

We got a new batch of PCB’s yesterday.

In the packet were two new board designs and a revision to a favourite.

We’ll start with the new boards:

MiniPiio MIDI – MIDI In and Out functions with a pin header to wire straight to your DIN connectors,

MinIPiio Expander2 – A new carrier board which takes two different MiniPiio boards, doubling your MiniPiio fun! It has a on-board 3.3V power supply and cut-able tracks in case you need to isolate or swap signals.

Our favourite MiniPiio ProtoBoard was given a size makeover to make it a standard 40 x 50mm MiniPiio footprint. This allows it to work with the new MiniPiio Expander 2 board.


GitHub – Schematics and BoM’s

November 11, 2012

You can find our latest schematics and BoM’s on GitHub at https://github.com/DTronixs.

We’ll be adding more files over the following days


MiniPiio L293D board v0.10

September 7, 2012

** UPDATE: You can get these boards at tindie.com in the DTronixs store **

Here’s the second of the new Raspberry Pi MiniPiio add-on boards.

This is a DC Motor controller using the venerable L293D from ST (and others). The L293D is dual H-Bridge driver capable of driving 36V DC and 600mA per H-Bridge.

The board was designed in Design Spark PCB and the schematic is here.

Here’s the L293D board fitted to a Raspberry Pi:

and here’s the L293D and RPi driving a pair of small DC motors. Hope fully this will be a small robot in time for e-day the Newcastle Maker Space is talking part of at Gateshead Central Library on 29th September.


MiniPiio Relay2 Board v0.10

September 7, 2012

** UPDATE: You can get these boards at tindie.com in the DTronixs store

I meant to post this a few weeks back but holidays etc. got in the way, so here it is now.

So here we have a simple two relay DPCO board. Either of the relays can be selected from 8 off the GPIO pins from the Raspberry Pi expansion header.

Circuit schematic is here

and here it is on a Raspberry Pi


MiniPiio PCB (Batch #2) board’s arrive

August 8, 2012

We received our second batch of PCB’s from our manufacturer today.


In the package were 4 sets of blank PCB’s for the MiniPiio boards: MiniPiio_RS232 (v0.2) , MiniPiio_ULN2803 (v0.2) and two new board MiniPiio_Relay2 and MiniPiio_293D.

MiniPiio_Relay2 is a two relay board with dual change over relays and MiniPiio_293D is a Full-H Bridge motor controller based on the venerable 293D chip. More details to follow.


MiniPiio ProtoBoard v0.10

July 2, 2012

** UPDATE: You’ll be able to get these boards soon at tindie.com in the DTronixs store

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:


Raspberry Pi Protoboard SM (V0.10)

June 25, 2012

** UPDATE: You can get these boards at tindie.com in the DTronixs store

We replaced the previous RPi Protoboard (v0.2) design with this new board design.

We’ve simplified the boards design by remove the 2.1mm power jack socket for using an external PSU wall adapter and the various jumpers and opted to use the Raspberry Pi’s own 5V supply instead. This means any circuit we build will be limited to the current we can source from the RPi supply but it should be good for up to 500mA with a decent wall adapter plugged into the RPi micro USB power socket. We also used surface mount components (hence the SM in the boards name) for all the components except for the connectors.

You’ll find the schematic is RPi_ProtoBoard_sm 0v10


MiniPiio DIO16 v0.10

June 24, 2012

** UPDATE: You can get these boards at tindie.com in the DTronixs store

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


MiniPiio ULN2803 v0.10

June 24, 2012

** UPDATE: You can get these boards at tindie.com in the DTronixs store

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.


MiniPiio RS232 v0.10

June 24, 2012

** UPDATE: You can get these boards at tindie.com in the DTronixs store

As promised we spent our weekend building the other MiniPiio designs. So without any further ado, here’s the MiniPiio_RS232.

This is for anyone who wants a RS232 port on the Raspberry Pi but doesn’t want to give up one of the two precious USB ports or clutter their desk with a USB hub to use a USB to RS232 adapter.

Unfortunately, there’s a mistake in the dimensions of the PCB. Instead of being 50 x 40mm like the other MiniPiio’s, the MiniPiio_RS232 is 45 x 42mm so its wider and shorter than the others. Being shorter is not a problem just ask Napoleon, but being wider does mean it interferes with the RCA Composite Video connector. 30-seconds with a file cuts it down to size but it does mean back to the drawing board or rather Design Spark PCB.

It was easy to fix, but just means another trip to the PCB manufacturer for another batch of boards. A PDF for the schematics is here.