BAW!! #2 TINYMCU

I have always love Micro-controllers (MCUs') I find the fascinating the idea that there is a complete computer on one thin slice of silicone, including RAM, storage and peripherals. And these device can be small super small in fact.

On MCU I have had my eye on for a while is the Atmel Attiny10. Well I'll correct myself its now the Microchip Attiny10 as Atmel where bought out by Microchip a couple of years ago.

Name

Value

Program Memory Type

Flash

Program Memory Size (KB)

1

CPU Speed (MIPS/DMIPS)

12

SRAM Bytes

32

Capture/Compare/PWM Peripherals

1 Input Capture, 1 CCP, 2PWM

Timers

1 x 16-bit

Number of Comparators

1

Temperature Range (C)

-40 to 125

Operating Voltage Range (V)

1.8 to 5.5

Pin Count

6

Source taken from Microchip.com

Though after starting this project I discovered the PIC10F320 and PIC10F322 have the same package and pint layout. Well at least for the SOT23-6 package. 

In the schematic I have decided to add as much debug/experimenting hardware as possible so to do this I have: 

• Added a jumper to enable the pull-up resistor for the reset pin (incase i would like to use the 4th IO line)
• Current limiting resistors on all the IO lines ( Just good practise to avoid drawing too much current from such a tiny device each IO allows a maximum of 40mA per pin)
• Indicator LED's (so I can get instant feedback on the pin status)
• Jumpers to enable and disable LED's ( I have made these pin jumpers so I can use the raw pins if needed for the ADC and CLK lines if needed.)
• Programming Header (make life easy)
• Power indicator LED (Got to make sure there is life :) )
• No Voltage regulator ( i want to be able to set my own voltages I would love to see how the device performs at the low end of its voltage range)

Don't forget all schematics and design files can be found at https://github.com/rabid-inventor/board-a-week  

Once I started to route the traces I discovered that the board may be able to have a single sided design. 

I rotated the MCU to try an make routing easier.

It was all going so well when I got to one last airwire. BUT:

As much as I single sided heaven is not happening. And jumper wires would be cheating. Time to 'ripup *' #BAW pic.twitter.com/yNBlhw5zu8

— Gee Bartlett (@rabid_inventor) July 22, 2018

Unfortunately the board was getting messier and messier just to make it single sided (see the bottom left corner of the board), and to get any further meant making the board size bigger and routing more around the edge. I was unfortunately time to admit defeat and route the board 2 layer.

20 mins later I had it all routed.

The design is now finished and ready to be sent for production. I'm really looking forward to having this one made, and be able to see what is possible with this tiny MCU.

I have also added a CC-BY commons licence please feel free to take a look and comment. Let me know what you think.