M81 - Mezzanine Card with 16 Digital Opto-Relay Outputs

The mezzanine card M81 is a 16-channel fully isolated, fully protected digital output M-Module for industrial applications. The outputs can switch DC as well as AC voltages and can also be used for analog signals. The M81 works with parallel transmission and supports very fast, spike-free switching.

The M81 switches relays, lamps or other loads. Typical I/O applications include automated test equipment, simulators and PLC-like applications.

The M81 is software-compatible with M27.

The M81 is based on the M-Module ANSI mezzanine standard. It can be used as an I/O extension in any type of bus system, i.e. CPCI, VME or on any type of stand-alone SBC. Appropriate M-Module carrier cards in 3U, 6U and other formats are available from MEN or other manufacturers.


  • 16 opto-relay outputs
  • 0 V to 36 V output voltage per channel
  • 500 mA output current per channel
  • Thermal and short-circuit protection
  • 500 V DC isolation from the system
  • 100 V DC isolation between the channels
  • -40 °C to +85 °C


Digital Output Characteristics
  • Output Voltage: 0 V to 36 V
  • Output Current: 500 mA max. per channel
  • Switching Times
    • Turn-on time: 700 µs typ.
    • Turn-off time: 40 µs typ.
  • Thermal and short circuit protection
  • Outputs are designed for AC and DC operation
  • Digital I/O
    • 16x digital output, isolated, HD-Sub, 44-pin, receptacle
  • M-Module
    • 1x A08/D16/IDENT, board to board
Product Standard
M-Module: ANSI/VITA 12-1997 (S2012)
Electrical Specifications
  • Supply voltage
    • +5 V (-3%/+5%)
  • Power consumption
    • 1.65 W max.
  • Isolation voltage:
    • 500V DC between isolated side and digital side
    • All channels are optically isolated
Mechanical Specifications
  • Dimensions standard: M-Module: (W) 149 mm, (D) 53 mm
  • Weight: 72 g
Environmental Specifications
  • Operating temperature
    • 0°C to +60°C or -40°C to +85°C
    • Airflow: min. 10 m³/h
  • Storage temperature: -40°C to +85°C
  • Relative humidity range (operation): max. 95% non-condensing
  • Relative humidity range (storage): max. 95% non-condensing
  • Altitude: -300 m to + 3000 m
  • Shock: 15g/11ms
  • Bump: 10g/16ms
  • Vibration (sinusoidal): 2g/10 Hz to 150 Hz
  • Conformal coating on request
PCB manufactured with a flammability rating of 94V-0 by UL recognized manufacturers
  • EN 55022 (radio disturbance)
  • IEC 61000-4-2 (ESD)
  • IEC 61000-4-4 (burst)
MTBF: 1 200 000h @ 40°C (derived from MIL-HDBK-217F)
Software Support