MAXREFDES174#: IO-Link Distance Sensor


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The MAXREFDES174# is a complete, high-accuracy, IO-Link® distance sensor reference design that provides accurate measurements for distances up to 4m. Built in an industrial form factor, the reference design makes use of a commercially available time-of-flight (ToF) laser-ranging sensor.

In this design, a Renesas RL78 (R5F10E8EALA) microcontroller interfaces between the distance sensor and the MAX22513 IO-Link device transceiver. The MAX22513 features an internal high-efficiency DC-DC buck regulator, two internal LDOs, and integrated surge protection for robust communications in a very small PCB area without requiring external protection components, such as TVS diodes. The MAX22513 is in a 28-pin TQFN package, allowing the MAXREFDES174# to have a tiny footprint of just 1.2in (3cm) in length. The design is reverse-polarity protected using the integrated active reverse-polarity protection of the MAX22513. The internal DC-DC buck regulator significantly reduces power dissipation, and the two integrated LDO regulators in the MAX22513 generate 3.3V and 5V, which reduces the number of required external components and saves space. The MAX22513 also features low on-resistance drivers (C/Q and DO/DI) to further reduce power dissipation, allowing this reference design to consume minimal power with very low thermal dissipation.

This sensor utilizes the IQ2 Development® IO-Link device stack to communicate to any IO-Link version 1.1-compliant master. The board contains a male M12 connector for connecting to a compliant IO-Link master using a standard M12 cable. Connecting the MAXREFDES174# to a USB IO-link master, such as the MAXREFDES145#, with the associated software allows for easy evaluation.

Design files, firmware, and software are available on the Design Resources tab. The board is also available for purchase.


  • IEC 61131-9 Compliant
  • IQ2 Development IO-Link Stack
  • IO-Link Version 1.1 Compliant
  • Measures Distances Up to 4m

  • MAXREFDES174# and the iqLink Master from IQ2 Development

    MAXREFDES174# and the iqLink Master from IQ2 Development

  • MAXREFDES174# system block diagram

    MAXREFDES174# system block diagram




Designed, Built, Tested

Board pictured here has been fully assembled and tested.


Details Section

Details Section


Advanced factory automation solutions (i.e., Industry 4.0) require an increasing number of smart sensors, which are typically controlled using IO-Link point-to-point serial communication between the sensor and controller (master). As a leading provider of IO-Link sensor transceiver and master transceiver ICs, Maxim also provides complete reference design solutions to help our customers improve their time to market. These proven designs cover all of the hardware and software requirements needed for compliance with the IO-Link standard. The complete reference design is provided on a 30mm x 7.5mm printed circuit board (PCB).

Maxim Integrated and IQ2 Development collaborated to design the MAXREFDES174# reference design that is compliant with the IO-Link version 1.1/1.0 standard. The MAXREFDES174# design consists of an industry-standard MAX22513 IO-Link device transceiver, a Renesas RL78 low-power microcontroller that uses the IQ2 Development IO-Link device stack, and a commercially available VL53L1 distance sensor.

Quick Start Guide

To test the MAXREFDES174# sensor, connect it to a port of an IO-Link master. In the following example, an iqLink IO-Link master is used, but any IO-Link compliant master and associated IO-Link device GUI should work.

Required Equipment

Supplied by Maxim:


Note: Download files from the Design Resources tab.

User Supplied:

  • IO-Link master (i.e., the iqLink) with an AC-to-DC 24V power adapter
  • iqPDCT IO-Link Device Tool Software
  • One IO-Link cable
  • Windows 7, Windows 8, or Windows 10 PC with a USB port



Master Setup Procedure

  1. Connect the MAXREFDES174# sensor to the IO-Link Master with an IO-Link M12 cable.
  2. Connect the IO-Link Master to the PC with a USB cable.
  3. Download and install the latest iqPDCT software from the IQ2 Development website (
  4. Download the IODD file for the MAXREFDES174# from the Design Resources tab or from the IQ2 Development website (
  5. The MAXREFDES174# comes programmed with firmware.

Sensor Testing Procedure

  1. Connect the female end of the IO-Link cable to the MAXREFDES174#.
  2. Connect the male end of the IO-Link cable to one of the ports on the IO-Link master.
  3. Open the iqPDCT software.
  4. Import the IODD file for the MAXREFDES174#.
  5. Press the Connect button.
  6. If communication is established correctly, the iqPDCT software shows the IO-Link master connection, the device tab blinks green, and the process data shows the current temperature, as shown in Figure 10.
  7. Apply a trigger to the sensor to continuously update the data as distance in millimeters.

Figure 10. MAXREFDES174# sensor found.


Input Type Vin(Min) Vin(Max) Iout(Max) Single/Multiple Output Vout(V) Pout(W) Isolated/Non-Isolated Topology
DC 24 - - - - - - -


Input Type DC
Vin(Min) 24
Vin(Max) -
Iout(Max) -
Single/Multiple Output -
Vout(V) -
Pout(W) -
Isolated/Non-Isolated -
Topology -

Maxim Devices (1)

Part Number Name Product Family Order Design kits and evaluation modules
MAX22513 Surge Protected Dual Driver IO-Link Device Transceiver with DC-DC Transceivers Buy Now Design Kits

Maxim Devices (1)

Part Number Product Family
Surge Protected Dual Driver IO-Link Device Transceiver with DC-DC

Design Files (6)

Title Type Size Date
maxrefdes174-assembly ZIP 1MB 2019-08-15
maxrefdes174-iodd ZIP 170KB 2019-08-15
maxrefdes174-pcb PDF KB 2019-08-15
maxrefdes174-schematic PDF 107KB 2019-08-15
maxrefdes174-bom PDF 102KB 2019-08-15
maxrefdes174 ZIP 2MB 2019-08-15
Date Type


(ZIP, 1MB)



(ZIP, 170KB)






(PDF, 107KB)



(PDF, 102KB)



(ZIP, 2MB)

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