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Week 8: Electronics Design

Group assignment:

  • Use the test equipment in your lab to observe the operation of a microcontroller circuit board (as a minimum, you should demonstrate the use of a multimeter and oscilloscope)
  • Document your work on the group work page and reflect what you learned on your individual page

Individual assignment:

  • Use an EDA tool to design a development board to interact and communicate with an embedded microcontroller

Group assignment:

  • What is a multimeter and what is it for?

The multimeter is also known as a tester, and consists of a portable electrical device that allows measuring the different electrical quantities that are part of a circuit, such as currents, powers, resistances, capacities, etc.

  • What is an oscilloscope?

The term oscilloscope is used to name the electronic measuring instrument for the visualization of electrical signals at a given time. These signals are expressed in graphs in which a beam of electrons passes through a coordinate axis on a phosphor screen

Technical specifications

  • Owon SDS7202 200MHz 1GS/s Deep Memory Digital Storage Oscilloscope, 2+1 Channel with VGA and LAN Interface
  • OWON SmartDS SDS7202 Digital Oscilloscope
  • Bandwidth: 200 MHz
  • Sampling rate: 1 GS/s
  • 10m recording length for each channel
  • 8 inch 800 x 600 pixel large screen

Conclusions

We learned that it is important to perform a calibration using the equipment’s own output values ​​or oscilloscope signals. Our initial mistake was not understanding why the sensor values ​​were so high and seemed incorrect. However, by realizing the importance of testing with the equipment’s own output first, we were able to obtain more accurate and realistic values.

Individual assignment:

  • Use an EDA tool to design a development board to interact and communicate with an embedded microcontroller

To create a board we use the Kicad 8.0 software. Once created we will connect with the ESP32 C3 Microcontroller.

STEP 1: We enter the following address to download the kiCad 8.0 software: https://github.com/KiCad/kicad-source-mirror/releases/download/8.0.0/kicad-8.0.0-x86_64.exe

STEP 2: We enter the kiCad 8.0 library in Git Lab and download it in code and then in zip

https://gitlab.fabcloud.org/pub/libraries/electronics/kicad STEP 3: We open kiCad 8.0 / file / new project STEP 4: We write the name of our sensor1 project and save it in a folder STEP 5: We write the name of our sensor1 project and save it in a folder and the following window will appear, then we click on the schematic editor STEP 6: We click on the symbol editor to add the libraries STEP 7: We go to file add library STEP 8: We choose global to add to all other projects. STEP 9: We select the kicad-master folder and locate the fab.kicad_sym file STEP 10: We verify that it already pulls the fab folder and we close STEP 11: We open the schematic editor, we are going to add symbols and then we choose the XIAO-ESP32C3 symbol and click accept STEP 12: We manage the fingerprint library in the main /preferences/manage fingerprint library STEP 13: We create the fab folder and look for the Fab.pretty folder to add the libraries STEP 14: Now if we start designing our card, for which we go to the schematic editor, in adding symbols we go to the fab folder and look for them to have 7 connectors STEP 15: We verify that it comes out in the following way and the idea is to create the board to connect to the quentorres STEP 16: We orient ourselves from the image to create our plate STEP 17: We are going to add power symbols and look for PWR_5V by writing 5V STEP 18: We locate the 5V with the mouse STEP 19: We do the same procedure with 3v STEP 20: We enter the preferred GND of the fab folder, to rotate we select the symbol and press the letter R so that it can rotate and the letter G to move STEP 21: We click on ESC to exit any tool and then with the mouse pointer we join the tracks STEP 22: Now we define that we are going to connect a proximity sensor STEP 23: We now add 4 connectors for which we go to add symbols / the fab folder / and look for the 4 connectors STEP 24: We mirror the 4-connector symbol STEP 25: Select the 5v symbol then CTRL + D to duplicate and move and then connect STEP 26: We add components, a switch and a resistor STEP 27: We add a 3v and GND STEP 28: We connect the 3V, the switch and the GND STEP 29: We enter a 1206 led and duplicate the GND with CTRL + D STEP 30: When it is joined it looks like this and we join it to pin 7 STEP 31: We click on verify fingerprints and we get that everyone has fingerprints STEP 32: We update the schematic plate and if we see that there are no errors we update STEP 33: In the schematic we see the xiao esp 32 and our board that we are working on STEP 34: We enter Edge Cuts and then draw a graphic polygon STEP 35: We click on the screen to show 3D viewer and we see that a moving image appears when we move the mouse STEP 36: To design the width of the tracks we are going to edit defined sizes STEP 37: The following window appears and in the + sign we add the thicknesses of the tracks, 1.2mm is recommended since current passes through that track STEP 38: We choose which track to work with in our case with the 1.2mm and then on the route tracks icon STEP 39: We click on a component and it automatically activates where to connect it STEP 40:They are left this way STEP 41: Now we go to mill it, for that we have to go to appearance and we choose to show all the layers without copper STEP 42: We export in SVG STEP 43: We choose F.Cu and we already have the file STEP 44: We change the Switch from 2 pins to 4 pins and follow the same process STEP 45: Entering the updated switch STEP 46: Con el cambio del switch termino asi We now use mods project to be able to print the plate

STEP 1: We enter the url https://modsproject.org/ right click programs STEP 2: We choose WILL 2D PCB STEP 3: We enter the SVG file STEP 4: We open the SRM-20 milling machine software where we calibrate the X, Y, Z axes at their 0 point then click on CUT to load the gcode generated by the MODS STEP 5: We start the plate milling process After trying so much with strawberries and srm - 20

Last update: May 26, 2024