Backplane Connector Decision

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 X
• JE – Don't know what systems are on boards yet, but I doubt you'll have much trouble with this

Max Current:

• At least X
• JE – Don't know what systems are on boards yet, but I doubt you'll have much trouble with this

Max Voltage:

• At least X (25V?)

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:

1. THC - Through Hole Connector (Easiest)
2. SMD - Wide Pitch (Not Complicated but requires additional equipment)
3. 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)