You've already forked bac-hardware
mirror of
https://codeberg.org/buildacubesat-project/bac-hardware.git
synced 2026-07-05 07:40:07 +00:00
98 lines
4.4 KiB
Markdown
98 lines
4.4 KiB
Markdown
# Utility Breadboard PCB
|
||
|
||
**Subsystem**: Utilities
|
||
**Status**: 🧪 Sample boards ordered for testing
|
||
|
||
**Design Files**:
|
||
- **Version**: v2r1
|
||
- **KiCad**: [`kicad10/`](kicad10/)
|
||
|
||
**Manufacturing Files**:
|
||
- **Version**: v2r1
|
||
- **KiCad**: v10
|
||
- **Date**: 2026-05-07
|
||
- **Release**: [utils-breadboard-v2r1](https://codeberg.org/buildacubesat-project/bac-hardware/releases/tag/utils-breadboard-v2r1)
|
||
- **Artifacts**:
|
||
- **Schematics**: No
|
||
- **Gerbers, Drill and Centroid**: Included (ZIP)
|
||
- **BOM**: Included (CSV)
|
||
- **Panel File**: Not Included
|
||
- **Instruction**:
|
||
- **Ordering**: Included (PCBWay: TXT)
|
||
- **Sourcing**: Included (DigiKey: URL)
|
||
- **Assembly**: Included (PCBWay: TXT)
|
||
- **3D Model**: Included (STEP)
|
||
- **3D Render**: Included (WebP)
|
||
|
||
|
||
|
||
## Overview
|
||
|
||
The Utility Breadboard PCB is a development and integration tool that breaks out bacBus signals onto standard 2.54 mm header pitch for prototyping on a breadboard. It supports bacBus pinout v4 and can be populated as either a bacBus A or B variant. Power rails (VBAT, 3V3 AUX, 3V3 MAIN, 5V MAIN) and all routable system signals are exposed, making it suitable for bench bring-up, subsystem integration testing, and firmware development.
|
||
|
||
Due to the 2-layer stackup, a subset of signals cannot be routed through (see [Known Limitations](#known-limitations--design-decisions)).
|
||
|
||
## Specifications
|
||
|
||
- **Dimensions**: 85 mm × 85 mm
|
||
- **Thickness**: 1.6 mm
|
||
- **Layer Count**: 2
|
||
- **Copper Weight**: 1 oz
|
||
- **Stackup**: PCBWay standard 2L
|
||
1. F.Cu — Mix
|
||
2. B.Cu — Mix
|
||
- **Impedance Targets**: Not controlled
|
||
- **Panelization**: No
|
||
- **Edge Cuts**: PCB edge cuts v3r1 (DXF: [`graphics/bac-pcb-v3r1-edgecuts.dxf`](graphics/bac-pcb-v3r1-edgecuts.dxf))
|
||
- **Mounting**: PCB Clamps, PCB Holders
|
||
- **Stacking**: bacBus connector on Ym edge using bacBus pinout v4; rotate 180° to use as bacBus B
|
||
- **ECAD**: Schematic and layout created in KiCad 9.0.8 and migrated to KiCad 10 for release
|
||
|
||
## Connectors and Interfaces
|
||
|
||
- **bacBus (A or B)**: Single bacBus connector on the Ym edge (bacBus pinout v4). The board is symmetric — install at 0° for bacBus A position, or rotate 180° for bacBus B position.
|
||
- **Power buses**: VBAT, 3V3 AUX, 3V3 MAIN, 5V MAIN broken out to 2.54 mm spaced, 1 mm diameter PTH
|
||
- **System signals**: All routable bacBus system signals broken out to 2.54 mm spaced, 1 mm diameter PTH
|
||
- **GPIO**: GPIO 9 and GPIO 10 broken out to 2.54 mm spaced, 1 mm diameter PTH
|
||
|
||
## Known Limitations & Design Decisions
|
||
|
||
- **2-layer routing constraints — reserved signals 2 and 3**: bacBus reserved signals 2 and 3 are not passed through due to routing constraints.
|
||
- **2-layer routing constraints — GPIO 3, 4, 11, 12**: GPIO lines 3, 4, 11, and 12 are not passed through for the same reason.
|
||
|
||
## Revision History
|
||
|
||
| Version | Date | Summary |
|
||
|---|---|---|
|
||
| v2r1 | 2026-05-07 | New PCB edge cuts v3r1 (85 mm × 85 mm); bacBus pinout v4; all routable system signals broken out; GPIO 9 and 10 broken out; VBAT, 3V3 AUX, 3V3 MAIN, 5V MAIN power rails exposed |
|
||
| v1r1 | 2025-05-14 | Initial release for bacBus v3rX |
|
||
|
||
## Notes
|
||
|
||
Sample boards have been ordered for testing. Manufacturing files reflect the as-ordered configuration. This board is not flight-qualified and is intended for development and integration use only.
|
||
|
||
## License
|
||
|
||
[CERN OHL-S 2.0](../../LICENSE)
|
||
|
||
## Contributing
|
||
|
||
Contributions to the _Build a CubeSat_ hardware ecosystem are highly appreciated! To keep things structured, here's how you can contribute:
|
||
|
||
### Fixes & Improvements to Existing Designs
|
||
1. Create a **new feature branch** (`git checkout -b feature/your-feature-name`)
|
||
2. **Commit** your changes (`git commit -m 'Brief description of change'`)
|
||
3. **Push** to the branch (`git push origin feature/your-feature-name`)
|
||
4. Submit a **Pull Request (PR)** with a clear description of the changes
|
||
|
||
### New Designs & Community Contributions
|
||
- Create your own repository
|
||
- Share a link in community discussions or open an issue
|
||
- If relevant, it will be referenced in the docs 🙌
|
||
|
||
## Supporting This Project
|
||
|
||
If you'd like to support the _Build a CubeSat_ project further, consider these options:
|
||
- [Patreon](https://www.patreon.com/buildacubesat)
|
||
- [KoFi](https://ko-fi.com/buildacubesat)
|
||
- [PayPal](https://tinyurl.com/bac-paypal-donation) |