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mPCIe-IIRO-8, mPCIe-RO-8, and mPCIe-IIRO-4

8 OR 4-Channel Isolated Digital Input and Relay Output with Change-of-State (COS) PCI Express Mini Card


  • PCI Express Mini Card (mPCIe) Type F1, with latching I/O connectors
  • 8 OR 4 optically-isolated non-polarized inputs
  • 8 OR 4 electromechanical 1A relay outputs
  • Change-of-State (COS) detection IRQ generation
  • 9” cable (228MM), standard
  • Panel-mountable isolation module with 37-pin male D-Sub connector
  • RoHS standard
  • Outputs with pulse/train / PWM / frequency / and Quadrature generation, Inputs with digital filtering and flexible measurement of pulse duration, frequency, and event counting, IRQ generation and more.
  • Available soon in M.2 form!
  • Designed, made, supported, and manufactured in the USA


  • Industrial operating temperature (-40°C to +70°C)
  • Support for Wind River VxWorks (call for ordering information)

The mPCIe-IIRO-8 consists of a type F1 PCI Express Mini Card (mPCIe) interface board that connects to a Mobile-ITX-sized, DB-37M Isolation Module via an included 9” cable. That module is designed to be easily panel-mounted in any application environment. It uses the high speed PCI Express bus to transfer digital data to and from the card. The digital I/O is compatible with 8255 PPI chips making it easy to program. This allows for simple and trouble-free migration from other ACCES PCI and PCI Express digital I/O cards, but also provides for advanced features enabled by the onboard FPGA logic.

The mPCIe-IIRO cards are well suited to complex environments, mitigating otherwise challenging ground-loops, high-common-mode, and transient voltage spikes common in electrically-noisy industrial or factory locations. The broad voltage compatibility and high current outputs allows use in a wide range of applications.

The non-polarized inputs support both AC and DC, and configuration jumpers allow 4.7ms input filters to be enabled per-channel, as desired – required for AC use. The isolated inputs support voltages from 3 to 31 VDC/VAC RMS [40Hz to 10000Hz], as well as standard 12/24 AC control transformer signals.

Outputs are 5 Form C (“Single-pole, double-throw”, or SPDT) and 3 Form A (SPST) electromechanical relays capable of 1A continuous-current load.

Change of State (COS) detection and interrupt capabilities are designed to relieve software from polling routines that can consume valuable processing time. Each port can be programmed for detecting state changes on their lines, in which any changes of the enabled port's bits (low-to-high or high-to-low) will generate an IRQ. An ISR (interrupt service routine) then determines which bit changed state and clears the interrupt.


The mPCIe-IIRO-8 is excellent for use in a variety of applications where on-board relays are required and inputs must be isolated. The mPCIe-IIRO-8 can be used in the following markets.

  • Process Monitoring
  • Manufacturing/Production Test
  • Machine Control
  • Monitoring and Control
  • Security Systems, Energy Management
  • Industrial Automation
  • Factory Automation
  • Laboratory Automation
  • Embedded OEM

Special Order

Please contact ACCES with your precise requirement. Examples of special orders would be conformal coating, custom software or product labeling, and more. We will work with you to provide exactly what is required.

Accessories and Connections

Available accessories include a variety of screw terminal boards for quick and easy connectivity as well as 2mm and 2.5mm mounting hardware. Alternately, custom hardware cables and/or interfaces can be produced to fit your specific application requirement.


The card is supported for use in most operating systems and includes a free DOS, Linux , and Windows 2000/XP/2003/Vista/7/8/10 compatible software package. This package contains sample programs and source code in Visual Basic, Delphi, and Visual C++ for Windows. Also provided is a graphical setup program in Windows. Linux support includes installation files and basic samples for programming from user level via an open source kernel driver. Third party support includes a Windows standard DLL interface usable from the most popular application programs, and includes LabVIEW 8.5+ VIs. Embedded OS support includes Windows XPe, WES7, WES8, vxWorks, etc. Full register-level documentation of all features ensures easy compatibility in any application environment.

Available Reference Manuals

Available Software Downloads

Available Datasheets

Drivers and Downloads

Full list of available Downloads: Software Packages, Drivers, Manuals, and other documents

Custom Software

ACCES also offers Custom Software Services for our products. Our prices are unbelievably low, often as inexpensive as free! If you need something tweaked to support your needs, or an entire enterprise application developed from scratch, it is definitely worth your time to inquire with us, first.

Further information about available ACCES Software:

Redistributing Windows Drivers
A list of ACCES drivers and the files that compose them under different versions of Windows, so you can easily redistribute ACCES cards and drivers.


ACCES has successfully partnered with Wind River to bring our entire line of PCI and PCI Express DAQ cards to VxWorks 7!

VxWorks 7 VxBus Gen 2 drivers, with easy-to-use API-libraries, are available for this product, including full source and sample code.

Designed to be compatible with our AIOWDM.dll Windows driver & API, this kernel module adds zero% CPU-cycle overhead to your VxWorks runtimes while allowing the lowest-latency hardware register access possible.

You can find more information about our VxWorks libraries and services on our Wind River Silver Partner page.

PC Interface

  • PCI Express Mini Card: Type F1 "Full Length" V1.2

Isolated Inputs

  • Number: 8 (or 4)
  • Type: Non-polarized, optically isolated from each other and from the computer (CMOS compatible)
  • Voltage: 3 to 31 DC or AC RMS (40 to 10000Hz)
  • Isolation: 500V channel-to-ground and channel-to-channel
  • Resistance: 1.8KΩ in series with opto-coupler
  • Filter Response
    • Rise-time: 4.7 ms
    • Fall-time: 4.7 ms
  • Non-Filter Response
    • Rise-time: 10 μs
    • Fall-time: 30 μs

Relay Outputs

  • Number: 8 (or 4)
  • Type: 5 Form C (SPDT) and 3 Form A (SPST), Ag with Au clad,single crossbar for mPCIe-IIRO-8; 4 Form C for mPCIe-IIRO-4
  • AC Load: 0.5A at 125 VAC (62.5 VA max)
  • DC Load: 1A at 24 VDC (30W max)
  • Switching Voltage: 125 VAC, 60 VDC, max
  • Switching Current: 1A max
  • Contact Resistance: 100 mΩ, max
  • Contact Life: 5 million operations, min


  • Temperature
    • Operating: 0°C to 70°C (order -T option for industrial temperature -40°C to 70°C)
    • Storage: -65°C to 150°C
  • Humidity: 5% to 95%, non-condensing
  • Power required: +3.3VDC @ 730ma (typical), all relays on


  • mPCIe card characteristics
    • Weight: 6.2 grams
    • Size
      • Length: 50.95mm (2.006″)
      • Width: 30.00mm (1.181″)
    • I/O connector
      • On-card: Molex 501190-4017 40-pin latching
      • Mating: Molex 501189-4010
  • Isolation board characteristics
    • Weight: 51.4 grams, (+11.2 grams for the 9" cable)
    • Size (Mobile-ITX sized)
      • Length: (2.952″)
      • Width: (1.1.772″)
    • I/O connector
      • On board: Male, D-Sub Miniature, 37-pin
      • Mating: Female, D-Sub Miniature, 37-pin

Regulatory Compliance

  • This product is designed to be in full compliance with CE requirements.

OEM and volume pricing available, please call us.

ModelPrice (USD)

mPCIe-IIRO-88-Channel Isolated Digital Input & Relay Output with Change-of-State (COS) PCI Express Mini Card
mPCIe-RO-88-Channel Relay Output PCI Express Mini Card
mPCIe-IIRO-44-Channel Isolated Digital Input & Relay Output with Change-of-State (COS) PCI Express Mini Card
mPCIe-HDW-KIT22mm mounting hardware $1
mPCIe-HDW-KIT2.52.5mm mounting hardware $1
ADAP37Direct connect screw terminal adaptor for use with 37-pin male connector $40
STB-37DIN-rail mountable screw terminal board for 37-pin connector $39
STA-3737-pin screw terminal board $29
CAB37-18Ribbon cable, female 37-pin connectors on each end, 18" $25
CAB37-36Ribbon cable, female 37-pin connectors on each end, 36" $29
CAB37MF-36Ribbon cable, male to female 37-pin connectors, 36" $29
CAB37FM-18Ribbon cable, male to female 37-pin connectors, 18" $29
Model Options (call for pricing)
-TExtended temperature operation (-40° to +70°C)
Acquisition, Control, Communication: Engineering and Systems