HardLabs

PCB Christmas Tree

reivax-boucoi·PCB_Christmas_Tree·Hardware/Kicad/christmas_tree.kicad_pcb

PCB Christmas Tree layout, top view — open source AVR/Arduino board by reivax-boucoi

About the PCB Christmas Tree

PCB Christmas Tree is an open source AVR/Arduino PCB design by reivax-boucoi, published on GitHub under the GPL-3.0 license. It is a 2-layer board measuring 88.7 × 98 mm, with 35 components from 17 distinct parts.

Its main chip is the ATTINY45-20SU, from the AVR/Arduino family. Other key parts include the TL431LP and TTP223. By type, the board carries 12 diodes, 10 resistors, 5 capacitors, 4 ICs, 2 connectors and 1 switch.

From the project

PCB Christmas Tree

Project was done in Kicad (yay for open-source !). Project files are here: , including the custom footprint library .

Components were chosen based on my current stock. Power storage: Instead of traditional batteries, 2 Maxwell 10F 2.7V supercapacitors were used as rechargeable storage, just because I have a bunch of them and don't like non-rechargeable gadgets. Granted, I estimated the tree can only run about 1 hour max per charge (approx. 6mA average current draw), which is not great considering a single CR2032 could probably last several weeks. But, supercaps are fun and you can recharge…

PCB Christmas Tree, from the project README
From the project README

Main components on the PCB Christmas Tree

TL431LPATTINY45-20SUTTP223

PCB Christmas Tree bill of materials (BOM)

35 components, 17 distinct parts — part numbers from the project's BOM.

QtyPartRefs
2
TL431LP
U1, U2
1
ATTINY45-20SU
ATtiny45-20SU
U3
1
TTP223
U4
1
USB_A
J1
1
Touch
J3
1
SW_SPDT_shield
SW1
1
VAL**
mouse-bite-2mm-slot
1
LED
D1
4
LED
D2, D4, D5, D7
7
LED
D3, D6, D8, D9, D10, D11, D12
2
10F
C1, C2
2
100N
100n
C3, C4
1
DNP
C5
2
100
R1, R10
2
12K
12k
R2, R4
2
280K
280k
R3, R5
4
220
R6, R7, R8, R9

PCB Christmas Tree design files

The KiCad project lives in the reivax-boucoi/PCB_Christmas_Tree repository on GitHub; these links point at the commit this page was built from.

PCB Christmas Tree: common questions

What microcontroller does the PCB Christmas Tree use?

The PCB Christmas Tree is built around the ATTINY45-20SU, from the AVR/Arduino family.

How big is the PCB Christmas Tree?

The PCB Christmas Tree measures 88.7 × 98 mm, has 2 copper layers and is 1.6 mm thick.

How many components are on the PCB Christmas Tree?

35 components, from 17 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.

Where can I download the PCB Christmas Tree design files?

From the reivax-boucoi/PCB_Christmas_Tree repository on GitHub, which has the KiCad layout and the BOM; the links under Design files point to each one.

Can I use the PCB Christmas Tree design in my own project?

Yes, under the terms of its GPL-3.0 license, which reivax-boucoi chose for the repository.

Can I test firmware for the PCB Christmas Tree without the hardware?

Yes. HardLabs builds a simulation of the board from its netlist and BOM, so you can run and debug AVR/Arduino firmware against it before you order a PCB.

Similar boards