4.Electronic Production

Background

What is PCB?

A Printed Circuit Board (PCB) is a flat board made of non-conductive material (usually fiberglass or composite epoxy) that is used to mechanically support and electrically connect electronic components using conductive pathways, or traces, etched from copper sheets laminated onto the substrate. PCBs are used in almost all electronic devices, providing a sturdy and reliable way to interconnect components such as capacitors, resistors, and integrated circuits. They can be single-sided (components on one side, traces on the other), double-sided (components on both sides), or multi-layered (with traces on multiple layers).

PCB fabrication methods

Tasks

This week has following tasks:

Group assignment: characterize the design rules for your in-house PCB production process send a PCB out to a board house.Here is our work of group assignments.

Individual assignment: make and test a microcontroller development board

Extra Credit Assignments: personalize the board,make it with another process

1. PCB Manufacturing using Milling

Milling: In this method, a CNC (Computer Numerical Control) machine is used to mill away the copper from a blank board, leaving behind the desired circuit pattern. This method is often used for prototyping and small production runs. For this first of all we need png image of the the circuit.For assignment this image we took from documentation.

Use of modsproject modsproject. Mods was originally written by Neil Gershenfeld (https://ng.cba.mit.edu/) for rapid-prototyping workflows in CBA research (http://cba.mit.edu) and classes (https://fab.cba.mit.edu/classes/MAS.863/), and for use in the fab lab network (https://fablabs.io/labs/map) and its classes(https://academany.org/). It is now served (https://modsproject.org) and supported (https://gitlab.fabcloud.org/pub/project/mods) as a community project. https://mods.cba.mit.edu now redirects to here; original mods remains available at https://mods.cba.mit.edu/oldindex.html

Sequence of use of the modsproject is as follows:



Import PNG



Select PNG



Read PNG

Open



Mill Raster 2D



Calculate: It calculates corresponding Numeric code.



Get calculation for cordinates



View:It downloads the .nc file which is readable for the milling operation.



Change extensions:Our machine is compatible with .gcd file extensions so .nc was renamed as .gcd

2.PCB fabrication at our FabLab

Our FabLab has MM3030 PCB milling Machine.its specifications are x=260mm, y=301mm,z=143mm.

We used multiple tools for the purpose of PCB manufacturing.

Following is the GUI of the MM3030 software.All blocks are explained in the image

Setting of origin x0,y0,z0

importing PNG.gcd file which we get from modsproject.This also shows the G code generated.

PCB milling in progress.Tool that I used is v tool for milling purpose.

Final PCB

3.Exploring the Xiao rp2040 microcontroller

I explored the rp2040 in arduino IDE. I used doucmentation provided by Adrián Torres. which is as follows:

Adding files in preferences

installing libraries

Selecting board and port

Compiling and uploading sketch

Code for LED blink

												#include <Adafruit_NeoPixel.h>
												
												int Power = 11;
												int PIN = 12;
												#define NUMPIXELS 1
												
												Adafruit_NeoPixel pixels(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);
												
												void setup() {
												  pixels.begin();
												  Serial.begin(9600);
												  pinMode(Power, OUTPUT);
												  digitalWrite(Power, HIGH);
												  pixels.show();
												  pixels.clear();
												  pixels.setPixelColor(0, pixels.Color(0, 0, 255));
												}
												
												void loop() {
												  pixels.show();
												  
												  if (Serial.available() > 0) {
													// Read the serial input
													char receivedChar = Serial.read();
												
													// Change the pixel color to red
													pixels.clear();
													pixels.setPixelColor(0, pixels.Color(255, 0, 0));
												  }
												
												  delay(400);
												}