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mPCIe-QUAD-8 and mPCIe-QUAD-4

PCI Express Mini Card Digital Quadrature Encoder / True-Pulse Input Cards


  • PCI Express Mini Card (mPCIe) Type F1, with Latching I/O Connectors
  • Direct Interface to Four or Eight Quadrature Encoders (A, B & Index (Z))
  • Single-Ended Or Differential 3V or 5V Encoder Inputs
  • 32-Bit Counters; Count Modes Include Quadrature (x1, x2, x4), Free-Run, NonQuadrature
  • (Up/Down), Non-Recycle, Modulo-N, and Range Limit
  • Selectable Clock Source (10MHz, 20MHz & 40MHz) (For Digital Filtering On Inputs)
  • Interrupt Generation From Various Status Changes
    • Select Flags for Interrupt Source (Instantaneous Or Latched)
  • Panel-Mountable DB-37F Four Channel Module
  • Two Modules Daisy-Chainable for Eight Quadrature Inputs (Two DB-37F Connectors)
  • 9” Cable(s) (228mm) Connect Between Quad Module(S) and mPCIe Card
  • Available in Industrial Temperature Operation (-40°C To +85°C), RoHS Standard
  • Designed, made, supported, and manufactured in the USA
  • Support for Wind River VxWorks (call for ordering information)

The mPCIe-QUAD-8 consists of a type F1 PCI Express Mini Card (mPCIe) interface board that connects to one or two DB-37F Modules via included 9” cables. The modules are designed to be easily panel-mounted in any application environment, and have convenient mounting holes for non-panel-mount applications. Up to eight differential (or single-ended) encoders (each with A, B, and Index) can be monitored simultaneously.

Type ISL32173 differential input circuits provide compatibility with a wide variety of quadrature encoder outputs.

The LSI/CSI LS7766 features:

  • 32-bit quadrature counters support x1, x2, and x4 counting modes, or can be used as non-quadrature up/down counters
    • Quadrature frequencies up to 9.6MHz
    • Non-quadrature frequencies up to 40MHz
    • Programmable index and marker flags (carry, borrow, sign & compare)
      • Enable/disable sources generating IRQ’s
    • Programmable count modes:
      • Normal (free-run) / Modulo-N / Range Limit / Non-Recycle, Binary / BCD

    The mPCIe-QUAD cards are well suited for use in industrial and embedded environments and factory locations.

    Special Order

    Please contact ACCES with your precise requirement. Example special orders include conformal coating, custom software or product labelling, and more. We will work with you to provide exactly what is required.

    Accessories and Connections

    Available accessories include
    ADAP37M-MINI37-pin Screw Terminal Board (direct plug-in) $40
    STB-3737-pin Screw Terminal Board (needs male-female ribbon cable)
    mPCIe-HDW-KIT2Mounting hardware for 2mm
    mPCIe-HDW-KIT2.5Mounting hardware for 2.5mm


    The card is supported for use in most operating systems and includes a free DOS, Linux (including macOS) and Windows compatible software package. This package contains sample programs and source code in C#, 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 VIs. Embedded OS support includes the family of Windows Operating Systems including IoT. 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

Quadrature Inputs

  • Counters: 8 or 4
  • Receiver Type: ISL32173
  • Configuration: Phase A, B, and Index; Single Ended or Differential
  • Sensitivity: ±200mV
  • Hysteresis: 30mV typical
  • Impedance: Internal 48kω minimum
  • Quadrature frequencies up to 9.6MHz
    • 4.5MHz when powered with 3.3VDC
  • Non-quadrature frequencies up to 40MHz when powered with 5VDC
    • 20MHz when powered with 3.3VDC


  • Operating Temperature:0°C to 70°C (order "-T" for -40°C to +85°C)
  • Storage Temperature:-40°C to 85°C
  • Humidity:5% to 95%, non-condensing
  • Power required:+3.3VDC @ 430mA using self power (+ encoder power); +5.0VDC @ 165mA with external power (+ encoder power)


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

Quadrature board characteristics

  • Weight:45 grams (+ 11.8 grams for the 9" cable)
  • Size: length: 2.835″ (72.01mm); width: 2.362″ (59.99mm)
  • I/O connector: On-module Female D-Sub Miniature 37-pin; mating: Male, 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)

Acquisition, Control, Communication: Engineering and Systems