

Mason
Shared projects
- Size
- 31.5 × 24.5 mm
- Copper layers
- 2
- Thickness
- 2.63 mm
- Parts
- 20
- Nets
- 48
- Pads
- 111
- Tracks, vias
- 181, 21
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 22 Nov 2024
- Updated
- 18 Mar 2026
Overview
Mason is an open-source printed circuit board by slvusd, from the slvusd/projects repository on GitHub. It is a 2-layer board of 31.5 × 24.5 mm with 20 parts on 48 nets, routed with 181 tracks and 21 vias.
It is built around the BNO055 and LP2985-33DBV. Its parts include 8 capacitors, 7 resistors, 3 ICs and 1 connector.
Main components
2BNO055
LGA-28(3.8x5.2)-40℃~+85℃ 2.4V~3.6V 40uA I2C、UART IMU X,Y,Z X,Y,Z ±16g ±2000dps LGA-28(3.8x5.2) Accelerometers ROHSBosch SensortecAccelerometersLP2985-33DBV
SOT-23-5-40℃~+125℃@(Tj) 1 150mA 16V 3.3V 30uVrms 45dB@(1kHz) 575mV@(150mA) 850uA Fixed Over Current Protection、Short Circuit Protection、Thermal shutdown、Enable control、Noise bypass terminal Positive SOT-23-5 Voltage Regulators - Linear, Low Drop Out (LDO) Regulators ROHSTexas InstrumentsVoltage Regulators - Linear, Low Drop Out (LDO) Regulators
README
README.mdProjects
The purpose of this repo is to sync teacher and student work to a repo so it can be shared and so it will not get lost.
To add a new computer to this repo, run these commands:
git config --global user.name slvusd-gitbot
git config --global user.email "ebrown+gitbot@slvusd.org"
git config --global credential.helper storeThen from pi's home directory, run
git -c credential.helper= clone https://github.com/slvusd/projects.git srcYou will be prompted for the username (slvusd-github) and password. Get the password (token) from Mr. Brown.
You need to run $HOME/src/git_sync.sh once from the
command line and enter the same credentials in order
to have the credentials cached for cron.
Finally, run crontab -e and add the following entry:
*/5 * * * * /home/pi/src/git_sync.shThat's it!
Parts
20| Qty | Value | Footprint | References |
|---|---|---|---|
| 4 | 0.1µF | Capacitor_SMD:C_0603_1608Metric | C5, C6, C7, C8 |
| 3 | 10k | Resistor_SMD:R_0603_1608Metric | R5, R6, R7 |
| 2 | 1µF | Capacitor_SMD:C_0603_1608Metric | C1, C2 |
| 2 | 4.7k | Resistor_SMD:R_0603_1608Metric | R3, R4 |
| 2 | 5.1k | Resistor_SMD:R_0603_1608Metric | R1, R2 |
| 1 | 100nF | Capacitor_SMD:C_0603_1608Metric | C3 |
| 1 | 10µF | Capacitor_SMD:C_0603_1608Metric | C4 |
| 1 | BNO055 | Package_LGA:LGA-28_5.2x3.8mm_P0.5mm | U1 |
| 1 | LP2985-3.3 | Package_TO_SOT_SMD:SOT-23-5 | U3 |
| 1 | MCP2221AxML | Package_DFN_QFN:QFN-20-1EP_4x4mm_P0.5mm_EP2.5x2.5mm | U2 |
| 1 | USB_C_Receptacle_USB2.0_14P | Connector_USB:USB_C_Receptacle_Amphenol_124019772112A | J1 |
The 19 most common of 20 parts.
Questions
How big is the Mason PCB?
It measures 31.5 × 24.5 mm and has 2 copper layers, 2.63 mm thick.
What parts does the Mason use?
20 parts, built around the BNO055 and LP2985-33DBV. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Mason KiCad files?
From the slvusd/projects repository on GitHub, at the commit this page was made from: the board is mason/PCB.kicad_pcb and its schematic mason/Float-2026.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Mason design in my own project?
Its repository states no licence, so its author keeps all rights: ask slvusd before reusing the design.
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