oresat-adcs-hardware/mezzanine-flex-board

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**OreSat Reaction Wheel Flex Board**	**Fabrication and Assembly Information**\ For build TIME-STAMP	10pt	margin=0.5in	true	2	true	blue

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About this Board

Board Description

This flexible circuit board connects the OreSat Reaction Wheel boards (the boards that control each reaction wheel) to the the OreSat RW Card, which handles the OreSat Power Domain for each RW. For more information, see the open source OreSat CubeSat system

Documentation Links

• Git repository: https://github.com/oresat/oresat-adcs-hardware
• TODO: Link to Design Notes + Design Review Notes

Documentation Files

Filename	Notes
README.pdf	This README file
PROJECT-NAME-outline.dxf	Board outline (with holes) in DXF format
PROJECT-NAME-pcba.step	3D model of PCBA (with components)
PROJECT-NAME-render-bot.jpg	Render of the top of the 3D model
PROJECT-NAME-render-bot.jpg	Render of the bottom of the 3D model
PROJECT-NAME-schematic.pdf	PDF of board schematics

Contact Information

• Website: https://www.oresat.org/
• Email: oresat@pdx.edu
• Instagram: @pdxaerospace

Board Renders

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Printed Circuit Board (PCB) Fabrication Information

Board Info

• 2 layer board
• Bounding box is 41.0 x 10.2 mm
• Board thickness uses 50um dielectric thickness
• There are two PI (Polyimide) stiffeners on the TOP surface of the assembly

Board Requirements

• Design Rules
  • Minimum Trace / Space design rules
    • Outer layers: 0.127 mm (5.0 mil) / 0.127 mm (5.0 mil)
    • Inner layers: 0.127 mm (5.0 mil) / 0.127 mm (5.0 mil)
  • Outer dimension router tolerance: +/- 0.254 mm (10.0 mil)
  • Hole placement tolerance: +/- 0.075 mm (3.0 mil)
  • Inner tab routed slot tolerance: +/- 0.254 mm (10.0 mil)
• Drills
  • Drill Positional Tolerance: 0.051 mm (2.0 mil)
  • Drill Size tolerance: +/- 0.064 mm (2.5 mil)
• Plated/Un-plated holes
  • PTH minimum diameter: 0.3 mm (11.8 mil)
  • PTH minimum annulus: 0.2 mm (7.9 mil)
• Outline/Routing
  • No requirements
• Slots
  • There are no slots.
• Cutouts
  • There are no cutouts.
• There are no fiducials.
• Panel tabs ("mouse bites")
  • No requirements; prefer that board edges are smooth; no mouse bites or other intrusions into the card outline.
  • If external mouse bites are required, minimize and customer will remove by hand before assembly.
• If not otherwise specified, build to IPC 6012 Class 2 or better.

Materials

• No controlled impedance.
• Outer layers must be 1 oz Copper.
• Polyimide flexible circuit material
• Board Surface treatment should be ENIG, althogh immersion Silver is acceptable.
• White silkscreen on top and bottom surface
• Any soldermask on top and bottom, no requirements for color.

Suggested Stack Up

Layer	Thickness	Notes
Top Copper	0.043 mm / 1.69 mil	Layer 1 foil, 1 oz Cu after plating
PI Core	0.050 mm / 1.96 mil	Polyimide flex material
Bottom Copper	0.043 mm / 1.69 mil	Layer 2 foil, 1 oz copper after plating

Array / Panel Information

• No panel or array required.

Fabrication Files

IPC-2581 File

Filename	Notes
PROJECT-NAME-ipc2581.xml	IPC-2581 board information file

Legacy PCB Files

Filename	Notes
PROJECT-NAME-Edge_Cuts.gbr	RS274X file for the dimension (outline) layer
PROJECT-NAME-F_Silkscreen.gbr	RS274X file for the top silkscreen
PROJECT-NAME-F_Mask.gbr	RS274X file for the top soldermask
PROJECT-NAME-F_Cu.gbr	RS274X file for the top copper layer
PROJECT-NAME-B_Cu.gbr	RS274X file for the bottom copper layer
PROJECT-NAME-B_Mask.gbr	RS274X file for the bottom soldermask
PROJECT-NAME-B_Silkscreen.gbr	RS274X file for the bottom silkscreen
PROJECT-NAME-User_Stiffeners.gbr	RS274X file for PI stiffener
PROJECT-NAME-PTH.drl	Excellon file for plated through holes

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Printed Circuit Board Assembly (PCBA) Information

Assembly Info

• There are SMT components on the bottom side of the board.

Assembly Requirements

• Assemble to IPC Class 2 or better
• Bake components that are not moisture sealed to appropriate levels as required.
• Solder paste MUST be leaded.
• Aqueous flux and wash strongly preferred.
  • Clean to NASA Standard "Visibly Clean (VC)": No particles or residues are visible to the naked eye.
• No conformal coating.
• Ship in antistatic protective bag

Component Specific Assembly Information

• No specific requirements.

Assembly Files

IPC-2581 File

Filename	Notes
PROJECT-NAME-ipc2581.xml	IPC-2581 board information file

Bill of Materials (BOM)

Filename	Description
PROJECT-NAME-bom.csv	BOM in Comma Separated Variable format

Solder Paste Stencils

Filename	Notes
PROJECT-NAME-B_Paste.gbr	RS274X file for top/front solder paste stencil
PROJECT-NAME-F_Paste.gbr	RS274X file for bottom/back solder paste stencil

Mounting/Placement Location

Filename	Description
PROJECT-NAME-3u.pos	Pick and place locations for components