Week 6  Electronic Design

 

Assignment – Redraw  the echo hello world board adding a button and led

 

Having no previous experience of electronics I started by following the very helpful tutorial and the cadsoft tutorials on how to use Eagle. Both were fairly easy to follow but I did come across problems when I checked the Design Rules and various errors came up so had to take much appreciated advice on how to resolve these.

 

 

The schematic and board are shown below

 

 snapshot_eagleschematic

 

tracesimage


I then exported the .png files and opened Gimp to adjust sizing and add a border.

 

Milling using the Modela


Milling the board took some time as I had to review how to set  x and y because the border for cutting the board was a bit tight and the settings had to be exact so I got lots of practice on the Modela which I'm sure will be very useful in the weeks to come.

 

Stuffing the board

I reviewed Neil’s class page to help me identify and find all the parts to stuff the board, I found this quite difficult and time consuming but with practice I’m starting to get the hang of sifting through the detail for helpful data eg which way round to place the switch and the led.

 

List of parts to solder to board and what to consider when placing on the board to solder

Attiny44A microcontroller

AVRISPSMD (AVRISP) 3 x 2  pin  DIL header

Led  (1206 mil a thousandth of an inch  size of LED)  LED’s have polarity the side with the line connects to ground

FTDI-Header powers the board - 6 x 1 single in line  SIL header 0.1 inch standard size space between pins

button OMERON 6mm switch Capacitor 1206    - 4 pins on 2 sides see data sheet to check layout on board

resistor 1206 x2 -  value of 10K

resistor value 499 OHMs

capacitor - value 1uf

20MHz resonator


Things learnt

I've learnt lots this week and still loads more to learn!

·      Give myself more space when designing the board

·      How to identify most components

·      More confident with soldering now

·      How to use eagle to design boards



 
            final board image

 
Files for my board design


button+LED_board_design