EKF - Short Profile
EKF - Short Profile


CompactPCI® Serial • Rear I/O Transition Module

Quad Port Isolated RS-485 Interface

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Block Diagram, Configuration

Block Diagram


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CompactPCI® Serial • Quad Port Isolated RS-485 Interface

Rear I/O Transition Module • Mezzanine Expansion Module

Proven and reliable, RS-485 (EIA/TIA-485) stays a popular fieldbus communication interface, due to simple installation via low cost twisted pair copper cables, up to 1200m length.

The SUB-RIO is basically a rear I/O transition module for CompactPCI® Serial systems. The board is equipped with four isolated rear panel RS-485 ports. High speed RS-485 balanced line transceivers with internal 5kV isolation barrier provide for optimum noise and EMC immunity.

In addition, the SUB-RIO can be configured as a mezzanine expansion module, suitable e.g. for the CompactPCI® Serial cards SU1-TWIST (isolated RS-485), SU2-BALLAD (isolated RS-232), SUA-RIO (isolated RS-232), and the SUB-RIO itself. When used as mezzanine board in addition to a carrier card, the SUB-RIO doubles the number of ports available from four to eight, and allows also mixed configurations RS-232 and RS-485.

When used as a rear I/O transition module, the SUB-RIO is equipped with the CompactPCI® Serial backplane connector rJ4, sourced from either the SU1-TWIST or SU2-BALLAD octal UART cards via P4 RIO.

When used as a mezzanine expansion module, the backplane connector rJ4 is not populated. Instead, TTL-level UART ports are passed via on-board stacking connectors M51 to M84, for either top or bottom mount assemblies, with a common 8HP rear (or front) panel.

The isolated RS-485 ports are wired to Micro-D rear (front) panel connectors, individually configurable for full-duplex operation (4+1 wire cable) or half-duplex (2+1 wire cable), either point-to-point or multipoint applications. As an alternate, the SUB-RIO can be equipped with classic D-SUB 9-pin connectors, attached by means of flat cable assemblies (on-board headers PU5 to PU8).


SUB-RIO Simplified Block Diagram

Block Diagram
Summary of Features

CompactPCI® Serial
  • PICMG® CompactPCI® Serial standard (CPCI-S.0)
  • Rear I/O transition module
  • CompactPCI® Serial backplane connector rJ4
  • Dimensions 100x80mm2 (3U), 4HP rear panel width
  • Suitable for CompactPCI® Serial octal UART peripheral cards SU1-TWIST and SU2-BALLAD (matching SU1 and SU2 backplane connector P4)
  • Expands front card to 8 ports in total (4 x front panel connectors, 4 x rear panel)
  • Any 4 + 4 port mix of isolated RS-232 and RS-485

Mezzanine Option
  • Mezzanine Expansion Module (rJ4 not populated)
  • Expands carrier card to 8 front (or rear) ports, 8HP total panel width
  • Suitable for CompactPCI® Serial octal UART peripheral carrier cards SU1-TWIST and SU2-BALLAD (8HP front panel assembly)
  • Suitable for rear I/O modules SUA-RIO and SUB-RIO (8HP rear panel assembly)
  • Stacking connectors M51 - M84, pass through, top or bottom mount
  • Any 4 + 4 port mix of isolated RS-232 and RS-485

RS-485 Transceivers
  • 5kV rms isolation barrier RS-485/RS-422 transceivers (Analog Devices ADM2682)
  • Configurable as half- or full-duplex
  • ±15 kV ESD protection on RS-485 input/output pins
  • Transceiver data rate 16Mbps max.
  • Connect up to 256 nodes on one PartyLine bus (driver enable control via dedicated UART mode select outputs)
  • Open- and short-circuit, fail-safe receiver inputs
  • High common-mode transient immunity >25 kV/µs
  • Thermal shutdown protection

Panel I/O
  • 4 x Rear or front panel Micro-D 9-pin high density male connectors
  • RS-485 ports isolated against each other and board circuitry
  • On-board DIP-switches for full/half-duplex setting, and line termination on/off
  • Micro-D cable assemblies available, e.g. Micro-D to classic style D-Sub male or female
  • Ordering option D-Sub 9-pin panel connectors (4 ports require 8HP F/P)
  • Option 2 x D-SUB9 panel connectors on request (4HP, 2 x micro ribbon flat cable assembly)
  • Option 3 x D-SUB9 panel connectors on request (4HP, handle replaced by knurled screw)
  • Option 4 x D-SUB9 panel connectors on request (8HP, 4 x micro ribbon flat cable assembly)

Environment, Regulatory
  • Designed & manufactured in Germany
  • Certified quality management according to ISO 9001
  • Long term availability
  • Rugged solution (coating, sealing, underfilling on request)
  • RoHS compliant
  • Operation temperature -40°C to +85°C (industrial temperature range)
  • Storage temperature -40°C to +85°C, max. gradient 5°C/min
  • Humidity 5% ... 95% RH non condensing
  • Altitude -300m ... +3000m
  • Shock 15g 0.33ms, 6g 6ms
  • Vibration 1g 5-2000Hz
  • MTBF 94.3 years
  • EC Regulations EN55022, EN55024, EN60950-1 (UL60950-1/IEC60950-1)

SUB-RIO Transceiver Schematics - FDX/HDX

Simplified Transceiver Schematics - Full Duplex

SUB-RIO Transceiver Schematics - FDX/HDX

Simplified Transceiver Schematics - Half Duplex

SUB-RIO Micro-D Connector Pin Assignment

Micro-D Connector Pin Assignment

SUB-RIO w. SU1-TWIST Assembly

SUB-RIO w. SU1-TWIST Assembly
Ordering Information
Please refer to List 21 for popular SKU
EKF is an ISO-9001 certified company
EKF Elektronik GmbH • Philipp-Reis-Str. 4 • 59065 Hamm • Germany
Phone +49 (0)2381/6890-0 • Fax +49 (0)2381/6890-90 • E-Mail