Overarching decision: Physically a backplane or practically a backplane?
- Do we want the backplane PCB to physically hold all other boards and they must slot in, or are wire connections OK?
Targets (Maximum/Minimums/Targets):
Pin Count:
- More is better, at least 22 at 3A, 34 at 1A
Max Current:
- See above
Max Voltage:
- At least 4S LiPo (17V)
Fabrication Method:
- Board-independent; connector functionality should not rely on certain mechanical characteristics of the PCB
- Reversible: connector should not be irreversible or irremovable, in event of damage
- Requires no specialized, high-cost tools.
- Bonus points; ability to act as a wire-to-board connector as well, for use in debugging.
Mechanical Connection:
- Keyed; the obvious one
- Positive latching; IREC compliance, resistance to vibration
Assembly Difficulty:
- THC - Through Hole Connector (Easiest)
- SMD - Wide Pitch (Not Complicated but requires additional equipment)
- SMD - Tight Pitch (Hard - Potential for shorts)
Part Availability:
- Bonus points if the connector is a basic part or carried by JLCPCB already.
- Reduces ordering complexity and potentially cost ($3 extra per each non-basic component) - JLC doesn't basic stock any connectors.
- https://jlcpcb.com/parts/componentSearch?isFirstLevel=true&firstName=Connectors
Cost (<$5 Per Connector)
Connector Name | #Pins | Max Current | Max Voltage | Fabrication Method | Mechanical Connection | Assembly Difficulty | Part Availability | Board Connection | Cost | Notes | Datasheet/Link | Mates with |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Molex Microfit | 2-24 | 8A | Lots | Crimp, PCB Mount | Plastic Latching | Low-Medium | Very High (3rd party equivalents) | Through Hole or SMD | <$0.1 | Generic automotive connector. Very sturdy, but take up a lot of board space. Available as WTB, BTB, WTW, Panel, etc. | https://www.molex.com/molex/products/family/microfit_30 | |
Molex EBBI Plug | 40 | 1A | 30V | Board to Board | Low | High (digikey) | Through Hole | $5-$10 | https://www.molex.com/molex/products/part-detail/pcb_receptacles/0716607040 | https://www.molex.com/molex/products/part-detail/pcb_headers/0716612540 | ||
2xN Header | 2xN | 4A-6A | 500V | None | Low | Very High | Through Hole | < | Generic 0.1" header, very interchangeable and cheap options available | https://www.mouser.com/ProductDetail/Samtec/TSW-150-08-S-D-RA?qs=rU5fayqh%252BE3IO3pomHat5g%3D%3D | ||
IDC Header | 3A | 350V | Crimp | Plastic Latching | Low | Very High | Through Hole | <$10 | Generic 0.1" header, very interchangeable and cheap options available | https://www.molex.com/molex/products/part-detail/pcb_headers/0901301240 | https://www.molex.com/molex/products/part-detail/crimp_housings/0901420040 | |
Samtec ERM8-030-01-L-D-RA-TR | 10-75 | 1.4A | 225V | Board to Board | None | Medium | Medium (Lots in stock) | SMD | $10 per | https://www.samtec.com/products/erm8-ra |