mPCIe-QUAD-8, mPCIe-QUAD-4, 8 & 4 Channel Quadrature Encoder Input mPCIe Cards

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  • 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, Non-Quadrature,(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
  • Available Now in M.2 form!
  • Designed, made, supported, and manufactured in the USA
  • Support for Wind River VxWorks (call for ordering information)

Factory Options

  • 2.75 inch cable between mPCIe-QUAD-8 quad boards
Last updated on December 13, 2023, 10:45 am


In Stock


The mPCIe-QUAD-8 consists of a type F1 PCI Express Mini Card (mPCIe) interface board that connects to two DB-37F Modules via included 9” cables.
The mPCIe-QUAD-4 consists of a type F1 PCI Express Mini Card (mPCIe) interface board that connects to one DB-37F Module via an included 9” cable.
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
      • 4.5MHz when powered with 3.3VDC
    • Non-quadrature frequencies up to 40MHz when powered with 5VDC
      • 20MHz when powered with 3.3VDC
  • 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 37-pin Screw Terminal Board (direct plug-in)
STB-37 37-pin Screw Terminal Board (needs male-female ribbon cable)
mPCIe-HDW-KIT2 Mounting hardware for 2mm
mPCIe-HDW-KIT2.5 Mounting 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.


Data Sheets



Drivers and Downloads

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

Information about our Free Software packages:

ACCES is proud to provide a full suite of software support with every Data Acquisition product. We are committed to supporting the most popular operating systems and platforms for our customers. Currently we are actively supporting XP -> 10, both 32 & 64 bit, including “Server 2008,” “Embedded,” and “Compact” flavors for all plug-and-play products including PCI, PCI Express, USB, and more. Many products continue to ship with support for additional operating systems such as DOS, Windows 95, 98, Me, NT4, and 2000.


Among the software we deliver with our products are sample programs in a wide variety of programming languages. These samples are used to demonstrate the software interfaces to our products — and many can be used as-is in your production environments, or to test functionality of the devices out-of-the-box. We’re currently actively supporting sample programs in Microsoft Visual C#, Visual Basic, Delphi, and Visual C/C++, with many devices including samples in Borland C/C++ 3.1 for DOS. Additionally we provide National Instruments LabVIEW compatible DLLs and many demonstration VIs for our devices.


Drivers for various operating systems are also provided, including active support for Windows XP -> 10 — all in both 32-bit and 64-bit flavors, and including consumer, server, and embedded varieties — as well as the 2.6 and newer Linux kernels and recent OSX / macOS versions. Many products continue to ship with driver support for Windows 95, 98, Me, NT4, and Windows 2000, but support for these operating systems is considered deprecated.

Setup Programs and Utilites

Our Data Acquisition devices also include a graphical setup utility that walks you through the process of configuring any option jumpers or switches on the device, as well as explaining a little about the various connectors present.

Many devices also include utility programs – little tools to make your use of the device easier, such as EWriter, a program that allows you to read and write data in the user-accessible EEPROM locations on all our USB data acquisitition products; or WinRISC, a “Really Incredibly Simple Communications” terminal program that lets you get started instantly with serial devices.

“Register Level” Documentation

Besides all this software in all these languages and operating systems ACCES has a policy of open and transparent development: none of our lowest-level “register” interfaces are hidden from you — we document every register in every bus card, every command in every serial board, and every usb control transfer in every USB Data Acquisition board. These lowest-level interfaces allow you to develop for our products in ANY operating system or language, regardless of our actively supporting it or having a driver for it. We have customers actively developing in ADA, Android, Python, Java, MATLAB, Solaris, and more, just by referring to our complete low-level interface documentation! And we provide the full source code to all of our drivers, regardless of operating system, to give you an even bigger head start in your own development tasks.

No Fees or Royalties

All of this software is provided at no additional charge, and is licensed under any of a variety of flexible — and royalty free — options. Check out our software license explanation if you’d like more information.

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

  • Receiver Type: ISL32173
  • Configuration: Phase A, B, and Index; Single Ended or Differential
  • Channels: 8 or 4
  • Common mode: -7V to 12V
  • Differential Inputs: -9v to 13V
  • Sensitivity: ±200mV
  • Hysteresis: 30mV typical
  • Impedance: Internal 48kω minimum


  • 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

mPCIe card 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.
ModelDescriptionPrice (USD)

4-Channel Quadrature Input PCI Express Mini Card


8-Channel Quadrature Input PCI Express Mini Card

mPCIe-HDW-KIT2 2mm mounting hardware $1
mPCIe-HDW-KIT2.5 2.5mm mounting hardware $1
ADAP37M-MINI Direct connect screw terminal adapter for use with 37-pin female connector $40
STB-37 DIN-rail mountable screw terminal board for 37-pin connector $39
CAB37MF-18 Ribbon cable, DB37 Male to Female, 18″ $29
Model Options (call for pricing)
2.75 inch cable between mPCIe-QUAD-8 quad boards
-T Extended temperature operation (-40° to +85°C)