PCB Pumpkin Soldering Kit - 2019

By Jamal Bouajjaj

Introduction:

This project is a PCB soldering kit in the shape of a pumpkin. The kit has been designed with some SMD and THT parts. If you plan to use this design as a kit for people who have no/minimal soldering experience, it is recommended to pre-solder the SMD parts before giving the board to them for them to solder.

Warnings/Issues:

Due to the original intent of this kit, it will have many reference to the University of New Haven and it's makerspace.
If you plan to use this kit for your own purpose, it is recommeded to update the PCB in Kicad to remove such marks. The same applies for all CAD drawings made in Autodesk Inventor 2018.

Project's folder:

Click the GitHub folder below to access the project's files, which include the KiCad PCB files, the Gerber files, and the Autodesk Inventor CAD files.

Pictures:

PCB Parts:

This kit has some THT and SMD parts to be soldered (THT means through-hole, and SMD means surface-mount).

PCB Reference	Part Description	Package Size	Quantity per Board
R1, R3	1kΩ Resistor	SMD-1206	2
R2	1MΩ Resistor	SMD-1206	1
U1	Attiny85	DPI-8	1
Q1	2N9304	THT	1
D1-D11	5mm LED	THT	11
R4-R14	68Ω Resistor	SMD-1206	11
C1 (Optional)	0.1uF Capacitor	SMD-1206	1
BT1	2xAA Holder	THT/Wire	1

Theory of Operation:

The circuit is based on an Attiny85 microcontroller. This microcontroller controls all LEDs at once with a 2N3904 transistor. There is a copper pad underneath the left eye, which serves as the capacitance touch pad. The CapacitiveTouch library is used in conjunction with a pre-determined threshold value to determine the when the pad has been pressed or not. When pressed, the Attiny changes the LED driving mode in software (from off, to fading, to blinking, then back to off).

Schematic:

Here is the PCB's schematic:

Technical Diagrams:

Here is some diagrams relating to the project:

Mounting:

The PCB is designed to be hanged from the hole at the tip of the pumpkin.

Programming:

The PCB is designed to be programed either by A) Pre-programming the Attiny85 in any means you like before placing it on the DIP socket, or B) use a Tag-Connect 6-pin pogo-pin connector following the pinout of J1 for reference (The pads are located at the stem of the pumpkin). The software can be found in the GitHub folder.