oresat-cfc-hardware/cfc-minibackplane

Oresat CFC Mini-Backplane

This is the backplane for UMBC's Air Harp 2 sensor, which is going to include a PIRT SWIR sensor using OreSat's CFC system.

Requirements:

• Match the DXF outline from Joe, including placement of connectors and the fastener holes.
  • Probably remove solder mask from both sides of those fastener holes just in case.
  • Probably put the external connectors in the upper right hand corner.
• Use an OreSat 20 pin debug connector on this backplane so we can run USB from the CFC processor to the external connector using the CFC processor's debug connector.
• External connections
  • Power should come through a 0.2 inch euroterminal for two 20 AWG wires.
  • USB should be via a Harwin M80-5400442 connector. Pin-out is determined by us.
    • signals: USB D+, USB D-, Vbus, and GND.
    • Vbus should go through a 10k ohm resistor between the 20 pin debug connector and the Harwin connector.

Required changes to the CFC Processor and CFC sensor boards

Easiest thing to do:

• Both OPDs should come on by default, so we need to bypass or hack the OPDs to turn on.
• We may want to figure out some way to power the local OPDs so they're not doing anything weird with their connections to the Octavo.

A Ben Idea:

• Add a 8.4V to 5V LDO, a Trinket M0, two 4.7K resistors, and use Oliver Rew's Arduino code to turn on both CFC cards
• This assumes we have Trinkets, which I believe we have a bunch lying around.
• This is cute because we don't have to modify the sensor or processor card, which I hate doing.
• Be careful of the 8.4V max input voltage can power the trinket without frying it (thus the 5V LDO).