Hardware/CubeSat RPi

From UIT
Revision as of 13:36, 3 December 2019 by Francois.corthay (Talk | contribs)
Jump to: navigation, search


This board is to serve an easy to use demonstrator for a CubeSat On-Board Computer (OBC). It hosts a Raspberry Pi Zero and a Microsemi ProASIC3 M1A3PE3000-2FG484I FPGA.

Power supplies

The board is powered from a standard 5 V ± 5% (4.75 V to 5.25 V).

This power supply is used by:

  • the Raspberry Pi which generates a 3.3 V for itself and for the FPGA I/O banks
  • a DC/DC converter which generates a 1.5 V for the FPGA core

The FPGA is supplied with:

Name function voltage
GND ground 0 V
GNDQ quiet ground 0 V
VCOMPLA/B/C/D/E/F PLL ground 0 V
VCC core supply 1.5 V
VCCIBx I/O supply 3.3 V
VMVx quiet I/O supply 3.3 V
VCCPLA/B/C/D/E/F PLL supply 1.5 V
VJTAG JTAG supply 3.3 V
VPUMP programming supply 3.3 V


Board to board

The inter-board connection is a serial bus with differential or coax (tbd) Tx and Rx lines. These channels are duplified for reasons of security. To this comes a 0 V and 5 V power supply.

The connection is done by a 4-pin connector on each corner of the board. Each corner transmits 0 V, 5 V and a differential or coax pair.

Raspberry Pi to FPGA

All Raspberry Pi I/O lines are connected to the FPGA. xxx of them are connected to the FPGA programming lines.


The Raspberry Pi Zero loads its operating system from the SD card.

The FPGA can be programmed either from the JTAG connector or from the Raspberry Pi. One has to make sure that the lines on the Raspberry Pi connector are tri-stated when trying to program the FPGA.

Personal tools