2.2 External Interfaces
2.3 Open VPX Backplane Interface
VPX Connectors
44 SBC622 Hardware Reference Manual
As noted in the Overview, the SBC622 board layout supports both conduction and
convection cooled mechanicals. This section provides an overview of the
functionality associated at each port, while detailed signal assignments on the
backplane connectors are provided in Appendix A: Connectors and Pinouts.
2.2.1 Form Factor
The SBC622 size and shape is 6U single height form factor per VITA 46.0.
The SBC622 supports both convection and conduction cooled operational
environment via build levels.
2.2.2 Electrical Interfaces
• RS422B/485A Interface
• Two balanced pair serial interfaces provided in accordance with
ANSI/TIA/EIA‐485‐A Mar 1998 and ANSI/EIA/TIA‐422‐B Jan 2000
• The RS485/422 interfaces support baud rates up to and including
115.2 kBaud
2.2.3 Power Entry and Distribution Definitions
The backplane VS1 and VS3 power rails are accessed by the SBC622 following the
functional requirements for VPX boards in VITA 46.0. This circuit also controls
the Power LED on the front panel of the assembly (See Section 1.9.2 LEDs on
page 36). Live insertion as defined in VITA 1.4 is not supported on the SBC622.
• The VS1 and VS3 rails are used for SBC622 circuits and at the PMC site. The
VCC_12V_AUX and VCC_‐12V_AUX rails are only used at the PMC sites.
Aggregate power load is expected to be 60 W maximum for the main SBC622
board, plus a maximum of 7.5 W for each of the PMC sites. Additional current
loading may be supported at the PMC site, to the limit of the backplane and PMC
site connector capacities.
VPX (previously known as VITA 46) (Versatile Protocol Switching) brings
switched fabrics to VMEbus‐based systems. VPX retains the existing 6U and 3U
form factors, supports existing PMC and XMC mezzanines, and maintains the
maximum possible compatibility with VMEbus.
P0, P1, P2, P3, P4, P5 and P6 connectors per VITA 46.0.