WEEK 8 - ELECTRONICS DESIGN
hero shot
PINOUT OF MY BOARD
after WEEK 4 - ELECTRONICS PRODUCTION and WEEK 6 - EMBEDDED PROGRAMMING lets dive into learning designing and basics of how electronics works..
assignment
group assignment
- use the test equipment in your lab to observe the operation of a microcontroller circuit board
- send a PCB out to a board house
Individual assignment
- use an EDA tool to design a development board to interact and communicate with an embedded microcontroller, produce it, and test it
extra credit: try another design workflow
extra credit: design a case for it
extra credit: simulate its operation
group ASSIGNMENT
You can find our group page here and this week group ASSIGNMENT here. we tested the design rules for different 3d printers in our lab
board we have MADE WITH THE boARD HOUSE
basic electronics
basics of electronics is all about concepts like inductance, capacitance, resistance, voltage and electrical currents. and how we use this to control electrons via manipulating, storing, switching, selecting, steering, carrying or resisting them.
modern digital electronics starts with invention of transistor in late 20th century.
"the invention that changed the world"
designing
i have previous EXPERIENCE of using lt spice and proteus during undergrad.
here i like to explore kicad for this week as #NEILGERSHENFELD suggested and it is open source too.i have kicad already installed in my system. it supports mac as well.
doing the schematics
download the fab kicad libraries and add it on kicad directory. kicad repo is recommeding to
Make sure you have at least KiCad 7 or greater installed. It works fine with Kicad 8.
Store it in a safe place such as ~/kicad/libraries or C:/kicad/libraries
i created a new project file named "week 8".now go to preferences>manage symbol libraries
and add "fab.kicad_sym" files as as symbol library. SIMILARLY go to manage footprint libraries and add fab.pretty as footprint library.
open .kicad_sch file and start drawing schematics. i added each module and its minimum circuits
for the voltage regulator circuit i REFERRED the below circuit as REFERENCE for reference
from circuits -DIY.COm
the schematics is done . make sure you label all pins APPROPRIATELY.
ALSO MAKE SURE YOU ARE ADDING COMPONENTS FROM FAB LIBRARY OTHERWISE IT WILL EFFECT THE FOOTPRINT OF THE COMPONENTS
main KEYBOARD shortcuts for kicad:-
W - wire
A - component
R - rotate
command+l - label
NOW WE NEED TO PROCEED WITH ROUTING..
routing
so now we are routing the wires in such a way we need it to get it milled.click the pcb editor option to go to the window
in the pcb editor window all the components and footprint will be be collapsed. you need to route each component carefully without colliding and by following the design constraints.
route wire to the pads required. blue line indicates pads to be connected.
in the baord settings set the milling design constraints as we tested in WEEK 4 - ELECTRONICS PRODUCTION of the roland mdx.
when routing its always better to route microcontroller>power supply>bootloader burning pins > other pads
while routing if you CHANGED some setting in schematics always update it in settings
for usb c we are using custom usb c module DEVELOPED by saheen palayi. so i changed the footprint of the default usb c i added in schematic and updated the design.
there were some errors and unconnected ground for me. i corrected it and checked drc again.it came clean.
now i need to export it in gerber file .
here plot, generate drill file adn map files.
these generated gerber file need to get be CONVERTED into png for milling.
gerber to png
gerber to png is a very easy to use gerber to png converter tool developed by our fablab kerala.
to use it open the webapp and drop you your gerber files
choose generate all option and click generate png.
wooolaah!!!!..... all you traces , outline and drills png are ready.
milling and soldering
milling process is DOCUMENTED in WEEK 4 - ELECTRONICS PRODUCTION . follow it and start milling the baord.
the milling came nice.
i sourced the components from our fabacademy inventory.
component with bom
proceeded with the soldering work . it is also DOCUMENTED in WEEK 4 - ELECTRONICS PRODUCTION week.
test
in order to test the pcb we can use the #Quentorres as a programmer.
THERE WERE PROBLEM WITH THE BOARD DESIGNED. custom usb c module HAD ITS PIN TX RX PIN INVERTED WHICH I DIDN'T KNOW I CAM E TO KNWO ONLY AFTER SOLDERING. SO I HAD TO USE JUMPER TO SOLVE THE ISSUE
boot loading
at first we need to install the firmware to the #Quentorres .
Step 1: Simultaneously press the "boot" and "reset" buttons. Connect your board to a computer using usb cable.Press and hold the "B" button, then while holding it, press the "R" button. Release both buttons, and the rp2040 will enter reset mode, exposing its flash memory as a hard drive.
Step 2: Transfer the uf2 file to the hard drive. Download the uf2 firmware file from here and place it onto the empty hard drive that appeared after completing step 1.
Once the file transfer is complete, the board will automatically reset.
Step 3: Confirm the board's functionality. To verify that the board is operational, ensure that it appears as a connected USB device. This device should advertise two USB endpoints: a serial port and an SWD programmer.
to flash the swd target which is our board in this case.
Using Arduino IDE with the Fab SAM core installed,
you can use the embedded edbg. To flash the bootloader on the target, click on Burn Bootloader:
8o
i succesfully bootlaoded the board.
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after BOOT LOADING i connected the board directly and uploaded a sample blink code.
running the blink code
3D PRINTING THE CASE
then i DOWNLOADED step file kicad after adding missing 3d files of the components from snap eda.
exported it into fusion and made a sliding case for it
final result after making casing
reflection
this is the first week i get to design a board myself which was a very enriching and empowering experience.