Week 8 - Electronics Production

Group Assignment:

characterize the design rules for your in-house PCB production process.

extra credit: send a PCB out to a board house

Here is our group assignment Link for this week.

Individual Assignment

Make and test the development board that you designed

To interact and communicate with an embedded microcontroller

Extra credit: make it with another process

In this week, we have to characterize the specification of PCB (Printed Circuit Board) production processes and have to learn about milling machines. In our lab, we have a Roland SRM-20 machine and this machine reads an rml file. For this we need to go to Mods,which changes png format into rml.

The machine: Roland SRM 20

Materials required:

PCB board (FR1 & FR2)

Double sided tape

Spatula

Tools

Milling bit - 1/64 used to mill the traces of the board.

Milling bit - 1/32 used to mill the edge of the board.

PCB PCB MILLING BY SRM-20.

For milling my PCB board I have used Roland SRM 20 machine.

Components I used to design my board.

ATtiny 1614

6 pin header connector for FTDI

3 pin header connector for UPDI

LED 2no

Resistor - 499ohm & 0ohm

Capacitor

Switch button

Workflow for MODS:

I have open Mods form this Link

Then Right click >> Go to programs >> click on open server program >> Under Roland you will find SRM20 >> Click on PCB PNG.

Then the ROLAND SRM 20 program will pop up as shown here;

To upload your design traces, click on select png file to upload.

After uploading png file, click on mill traces and click on calculate to view your traces.

Under Roland SRM-20 milling machine, set the origin XYZ to zero.

And delete this node as shown below.

Then right click >> click on module >> server module >> under file >> click on save. Then connect the output files of the Roland SRM20 milling machine to the input files of the save file

To mill outline or edge cute

Using SRM20

Turn on your SRM20 machine form the main power and make Ensure to close the front lid.

Open Vpanel software on the computer which is connected to the SRM20 machine and and set XY to zero under user coordinate system

Now set the Z axis to zero by loosening the spindle head with using allen key and tighten once your end mill tip touches the surface of PCB.

Go to Cut option in the VPanel to choose and upload file. Delete the existing file and add new file and start milling by clicking on OUTPUT.

Once the cut is finished, clean by vacuum and then lift it off carefully using a Scrapper.

Soldering my PCB.

Soldering is a joining process used to join different types of metals together by melting solder. Solder is a metal alloy usually made of tin and lead which is melted using a hot iron. The iron is heated to temperatures above 600 degrees fahrenheit which then cools to create a strong electrical bond.

components that i have used in my board.

Tools used for Soldering.

Here are some pictures that i took while soldering my PCB.

After soldering is done.

Programming the board

LED blink test

Open your Arduino IDE software.

To install Attiny1614 microcontroller, firstly you have to install megatinycore. So for that go to File >> Preference >> and add a url address in additional board manager urls.

Use this ULR: http://drazzy.com/package_drazzy.com_index.json

After that Go to tools >> select board >> board manager to install my board.

After that type megatinycore in search box and hit on install.

Now your board has been installed and to chose your board go to tools >> select board >> magatiny core and select Attiny1614 .

Now selected your chip by going to tools >> chip >> and select Attiny1614.

To do programmer you have to go to tools >> Programmer >> select SerilUPDI : SLOW

Then select your port to identify your board to do programming.

Finally i have used example to make my board blinking.

Here is my led blinking code that i used from example.

Programming the pushbutton

To programme the push button I used the example code from Arduino IDE and replaced the pin number. I used pin 2 for LED and 10 for push button.

Push button code

Final Video.

Electronics FAQs:

Q. What's a circuit?

A circuit is a closed loop that electrons can travel in. Such as a battery, provides electrical energy in the circuit.

Q. What is a load?

An electrical load is the component of the circuit that consumes energy or power. Which includes light bulbs and appliances.

Q. What is a conductor?

A conductor is a substance or material that allows electricity to flow through it.

Q. What is the difference between Voltage, Current and Resistance?

Voltage is the difference in charge between two points. Current is the rate at which charge is flowing. Resistance is a material's tendency to resist the flow of charge (current).

Q. What is Ohm’s Law?

Ohm’s Law states that the current through a conductor between two points is directly proportional to the voltage across the two points. Which states V=IR (R is constant)

Q. What does a Resistor do?

Resistor is actually a electronic component which limits the flow of electric current in a circuit.

Q. What does a Capacitor do?

A capacitor stores energy temporarily and can discharge the energy very quickly. They have high power densities.

Q. What does a Diode do?

A diode is a semiconductor device that essentially acts as a one-way switch for current. It allows current to flow easily in one direction.

Q. What does LED mean?

LED stands for Light emitting diode and it is a semiconductor device that emits light when an electric current passes through it.

Q. What is a Regulator?

Regulator is a electronic device which stabilize the output voltage or current of a power supply to a specific level despite variation in input voltage or load current.

Q. What is a Bypass Capacitor?

It is a capacitor that is placed between DC and ground to remove any AC components of the signal.

Q. What is a Current Limiting Resistor for an LED do?

The current limiting resistor limits the current for the LED and regulates the difference in voltage drops between the LED and the power supply.

Q. How are Capacitors used as High-pass and Low-pass filters? What does it filter?

The capacitors act as high-pass filters when they pass high frequencies and block DC(Direct current). The capacitors act as low-pass filters when they pass DC signals and block AC signals.Instead of placing the capacitor in series with the component, the capacitor will be placed in parallel. It filters out AC signals.

Q. What is VCC?

Voltage Common collector is the power input of the device.

Q. What is GND?

GND stands for Ground and it refers to a common reference point in an electronic circuit that has zero volts potential.

Q. What is Common Ground?

It is a Electronic devices that don't plug into a wall socket have a different type of ground usually called common ground. A circuit that runs on batteries will often use the battery's negative terminal as common ground - a reference point of zero volts compared to the battery's positive terminal.

Q. What is a Ground Plane and why is it used?

A ground plane on a printed circuit board (PCB) is a large area or layer of copper foil connected to the circuit's ground point, usually one terminal of the power supply. It serves as the return path for current from many different components.

Design Files:

Eagle Design

PNG File

Code File