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MAXREFDES200# is not sold as a standalone reference design. It is only available through the purchase of the MAXREFDES212#.

Go-IO Industrial IoT Reference Design

MAXREFDES212

Reference Design Disclaimer See the  Important Notice and Disclaimer  covering reference designs and other Maxim resources.

Description

Go-IO is an Industrial-Internet-of-Things (IIoT) reference design designed for rapid prototyping and development of configurable industrial-control systems. Typical end applications include Industry 4.0 driven process automation for building automation for intelligent buildings, smart sensors, reconfigurable industrial control systems, and robotics. All these industrial applications require a high performance, robust, configurable solution, which Go-IO provides using a modular approach. These systems are enabled by highly integrated ICs from Maxim Integrated, delivering new levels of performance while delivering lower power dissipation in tiny footprints.

Go-IO has four different boards. The different configurations provide a varying mix of type of I/O channels and communication interfaces to target different end applications.

Design files, firmware, and software can be found on the Design Resources tab. The boards are also available for purchase.

Features

  • Universal IO (UAIO), ±12.5V or ±25mA
  • 8 Digital Inputs, IEC 61131-2 compliant Types 1/3
  • 4 Digital Outputs, up to 1A with Safe Demag
  • IO-Link® Master, four ports, version 1.1 compliant
  • TMG IO-Link Master Stack
  • One RS-485 COM port, full duplex to 25Mbps data rate
  • Robust interfaces with integrated protection for ESD and surge

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Designed, Built, Tested

Board pictured here has been fully assembled and tested.

Details Section

Details Section


Go-IO is the brand name for a modular Industrial IoT reference design (see Figure 1) based on a carrier card (or backplane) (MAXREFDES215#), an application processor card (MAXREFDES211#), and an I/O card which can vary depending upon the target application (MAXREFDES200#, MAXREFDES201#). The MAXREFES200# targets factory automation and features a mix of I/O types including analog inputs, analog output, digital input, digital output, IO-Link and a RS-485 COM port. The MAXREFES201# targets motion control and features a mix of I/O types including digital inputs, DC motor drivers, encoders, and a RS-485 COM port.

All field connectors are on the MAXREFDES215# carrier card for easy connectivity to sensors, actuators, and communication ports. All cards are powered from a single 24V wall adapter, which connects to the carrier card. Circuitry on the carrier card generates various power rails including an isolated supply for the application processor card (MAXREFDES211#). Additional local on-card DC-DC converters and LDO regulators are used to create lower voltage rails specific to each card.

Order the MAXREFDES212# to receive a kit that contains the MAXREFDES215#, MAXREFDES211#, MAXREFDES200#, and a 24V wall adapter. The kit allows the Go-IO system to be used out-of-the-box.

Go-IO System Board Enlarge+

 

Diagram Enlarge+

System Diagram

When plugged together, the Go-IO boards form a configurable development reference design for industrial IOT applications. The system provides a robust, flexible architecture which leverages leading edge industrial technologies for Universal I/O, isolation, power management, and Arm®-based microcontrollers. Featuring highly integrated solutions, these boards support over 20 I/Os in a tiny footprint of less than three square inches. The compact footprint and high reliability are achieved by using highly efficient power management and low power dissipation devices, which are available in tiny packages.

Go-IO modular block diagram
Figure 1. Go-IO modular block diagram.

Detailed Description of the MAXREFDES215# Carrier Card

Introduction
Figure 2 shows the system block diagram for the MAXREFDES215#.


Figure 2. MAXREFDES215# block diagram.

Figure 3 shows the top view of the MAXREFDES215#.


Figure 3. MAXREFDES215# top view.

Connections
Two connectors are used for board-to-board interfaces: J1 and J2. J1 is an 80-way female connector that mates with a male connector on an I/O card, which can be either the MAXREFDES200# or the MAXREFDES201# depending upon the end application. J2 is a 30-way male connector that mates with a female connector on the MAXREFDES211# application processor card. Both connectors are keyed to prevent incorrect insertion of the respective cards.

Four M12 type female connectors are used to connect to industry-standard IO-Link sensors and actuators that use equivalent M12 male connectors and cables. Multiple screw terminal blocks are used for easy connection to the analog I/O, digital I/O and RS-485 ports.

Galvanic Isolation
The Go-IO uses two different domains, which are separated using the Maxim digital isolator products. The field domain uses the 24V input supply and 24V GND for reference. The logic domain uses APP_PWR and APP_GND for reference and is found on the application processor card, MAXREFDES211#.

Power Supplies
Power is supplied to the MAXREFDES215# using a standard 24V, 1A wall adapter that connects to the on-board barrel connector. Alternatively, a higher current power supply of up to 5A can be connected using screw terminals on block J9.

The 24V input rail is protected from overcurrent with a 1A fuse. If the MAXREFDES200# is used and if a higher current operation is required (i.e., digital output loads greater than 1A), an external 24V supply can be connected to the input terminal on connector J9. If the MAXREFDES201# is used with the DC motor drivers, the VMTR supply must be connected to the input terminal J3. The power supply must match the DC motor selected for voltage and current specifications.

With the 24V input, different DC-DC converters are used to generate different voltage rails. The MAX17681 is a high-efficiency iso-buck DC-DC converter used to provide isolated power up to 5W. In the MAXREFDES215#, the input is 24V and the MAX17681 uses primary-side feedback to regulate the output voltage while reducing the external components and saving total cost, no optocoupler required. After the transformer output and rectification, the MAX17608 current limiter provides the isolated power rails APP_PWR and APP_GND. The MAX17608 is the industry's smallest and most robust integrated system protection solution, providing 1A current limiting along with OV, UV, and reverse protection.

On the field domain, two regulators generate the higher positive and negative voltage rails, HVDD and HVSS, to be used by the analog IO products. The MAX17608 provides a protected 24V rail, V24_PROT, which in turn becomes the HVDD rail. The MAX15062 high-efficiency step-down DC-DC converter converts the +24V input to a negative voltage rail for use as the HVSS supply to be used by the analog IO products.

Detailed Description of the MAXREFDES211# Application Processor

Introduction
Figure 4 shows the system block diagram for the MAXREFDES211#.


Figure 4. MAXREFDES211# block diagram.

Figure 5 shows a picture of the top view of the MAXREFDES211#.


Figure 5. MAXREFDES211# top view.

Connections
The MAXREFDES211# connects to the underside of the MAXREFDES215# through a 30-way female connector that mates with a male connector on the MAXREFDES215# carrier card. Both connectors are keyed to prevent incorrect insertion of the respective cards. Three USB connectors are included for interfacing to the MAX32630 microcontroller.

Galvanic Isolation
The Go-IO uses two different domains, which are separated using the Maxim digital isolator products. The field domain uses the 24V input supply and 24V GND for reference. The logic domain uses APP_PWR and APP_GND for reference and is found on the application processor card, MAXREFDES211#. The digital isolators on the I/O control card, either MAXREFDES200# or MAXREFDES201#, perform the galvanic isolation function.

Power Supplies
Power is supplied to the MAXREFDES211# from the MAXREFDES215# (APP_PWR (24V) and APP_GND). On board regulators do a multi-level step down to provide the different voltage rails required by the microcontroller.

The MAX17502 DC-DC converter steps the 24V input down to 3.3V to use as the input to the two MAX1806 linear regulators. The MAX17502 high-efficiency, high-voltage, synchronous step-down DC-DC converter with integrated MOSFETs operates over a 4.5V to 60V input voltage range. This device is offered in a fixed 3.3V output voltage while delivering up to 1A of current. The output voltage is accurate to within ±1.7% over -40°C to +125°C.

The MAX1806 low-dropout linear regulator operates from a +2.25V to +5.5V supply and delivers a guaranteed 500mA load current with low 175mV dropout. The high-accuracy (±1%) output voltage has different preset values, and for the MAXREFDES211#, two MAX1806 linear regulators generate the 1.8V and 1.2V rails required by the MAX32630 microcontroller.

Microcontroller
The MAX32630 features an Arm Cortex®-M4 with FPU CPU that delivers ultra-low power, high-efficiency signal processing functionality with significantly reduced power consumption and ease of use. Multiple SPI, UART, I2C, 1-Wire® master, and USB interfaces are provided. The USB interfaces are made using industry standard FTDI USB chips.

The MAXREFDES211# uses four SPI buses to interface to the different peripherals:

  • MCU_SPI: Use the 2:1 jumper to select the target SPI bus, either a secondary FTDI-USB interface or the more commonly used APP_SPI1 bus. The APP_SPI1 bus connects to the 80-way connector to plug-in modules such as the MAXREFDES200# or MAXREFDES201#. This SPI bus is galvanically isolated on those cards and used to control I/O peripherals such as the MAX14819 IO-Link master IC.
  • APP_SPI2: The APP_SPI2 bus connects to the 80-way connector to plug-in modules such as the MAXREFDES200# or MAXREFDES201#. On the MAXREFDES200# or MAXREFDES201#, this SPI bus connects to the MAX22192, which is a galvanically isolated digital input device. The integrated isolation within the MAX22192 shares the isolated SPI bus with other field domain devices on the modules, saving the need for more external isolators.
  • WIFI_SPI: The WIFI_SPI bus connects to the Wi-Fi chipset and is unused in the initial product release.
  • SD_SPI: The SD_SPI bus connects to the SD card controller and is unused in initial product release.

Detailed Description of the MAXREFDES200# Factory Automation Module

Introduction
Figure 6 shows the system block diagram for the MAXREFDES200#.



Figure 6. MAXREFDES200# block diagram.

Figure 7 shows the top view of the MAXREFDES200#.


Figure 7. MAXREFDES200# top view.

Connections
The MAXREFDES200# connects to the top side of the MAXREFDES215# through an 80-way male connector that mates with a female connector on the MAXREFDES215# carrier card. Both connectors are keyed to prevent incorrect insertion of the respective cards.

Galvanic Isolation
The Go-IO uses two different domains, which are separated using the Maxim digital isolator products. The field domain uses the 24V input supply and 24V GND for reference. The logic domain uses APP_PWR and APP_GND for reference and is found on the application processor card, MAXREFDES211#. Three Maxim digital isolators perform the galvanic isolation function on the MAXREFDES200# I/O control card. The MAX14483 and two MAX14130 isolate the SPI buses and control signals (i.e., chip selects, R/W lines).

The MAX14483 is a 6-channel, 3.75kVRMS digital galvanic isolator using Maxim's proprietary process technology. The six signal channels are individually optimized for SPI applications and include very low propagation delay on the SDI, SDO, and SCLK channels. For the MAXREFDES200#, the MAX14483 isolates the APP_SPI1 bus to form the FLD_SPI1 bus that interfaces to the local MCU used for IO-Link master functionality.

The MAX14130 is a 4-channel, 1kVRMS digital isolator utilizing Maxim's proprietary process technology in smaller footprint QSOP packages. This product has four unidirectional channels making it ideal for isolating control signals.

The MAX14130 and MAX14483 transfer digital signals between circuits with different power domains at ambient temperatures up to +125°C. Independent 1.71V to 5.5V supplies on each side of the isolator also make the device suitable for use as a level translator, although this functionality is not used on the MAXREFDES200#. VDD_IO provides logic domain power for the isolators, which is generated by using the integrated LDO within the MAX22192. 3V3_MCU provides the field domain power for the isolators, which is generated on the MAXREFDES200#.

The MAX22192 provides additional isolation as an industrial, octal, digital input device with integrated isolation.

Power Supplies
Power is supplied to the MAXREFDES200# from the MAXREFDES215# (24V) and on-board regulators that step down to provide the different voltage rails required by the I/O devices and digital isolators.

The MAXM15462 is a high-efficiency, synchronous step-down DC-DC module with integrated controller, MOSFETs, compensation components, and inductor that operates over a wide input-voltage range. The module operates from 4.5V to 42V input and delivers up to 300mA output current over a programmable output voltage from 0.9V to 5V. The module significantly reduces design complexity, manufacturing risks, and offers a true plug and play power/supply solution, reducing time-to-market.

Two modules generate 3.3V outputs, 3V3_DIO for powering the I/O interfaces, and 3V3_MCU for powering the local MCU, the IO-Link masters, and the field supply for the digital isolators.

The MAX22191 has an integrated LDO which generates a 3.3V output from the 24V supply, to provide the rail VDD_IO.

IO Interfaces
The MAXREFDES200# has a range of digital I/O (DIO) and analog I/O as well as communication interfaces to represent the functionality commonly found within an industrial system, such as a Programmable Logic Controller (PLC) and its associated I/O modules.

Digital Inputs (DI)
The MAX22192 is an IEC 61131-2 compliant industrial digital input device with integrated isolation. The MAX22192 translates eight 24V current-sinking, industrial inputs to an isolated serialized SPI-compatible output that interfaces with 1.71V to 5.5V logic voltage. A current setting resistor allows the MAX22192 to be configured for Type 1, Type 2, or Type 3 inputs. In the MAXREFDES200#, the inputs are configured at Type 1 or Type 3. For proximity switches, the field wiring is verified using the wire break feature.

The MAX22192 has an isolated 4-pin SPI interface and the field-side accepts a single 7V to 65V supply to the VDD24F pin. When powered by the 24V field supply, the MAX22192 generates a 3.3V output on the VDD3F pin from an integrated LDO regulator, which can provide up to 25mA of current for external loads in addition to powering the MAX22192. In MAXREFDES200#, this output is the VDD_IO rail and is used to power the field domain of the standalone digital isolators, MAX14430 and MAX14483.

The MAX22192 isolates the SPI bus and provides field domain signals that allow other field domain SPI devices to be shared with the MAX22192 and to share its isolation channels. In the MAXREFDES200#, the daisy chained SPI bus is called FLD_SPI2 and connects to the digital output, analog I/O, and UART devices.

Digital Outputs (DO)
The MAX14912 is a digital-output, octal, high-speed, high-side switch/push-pull 24V driver capable of 200kHz switching rate. The MAX14912 has eight 640mA smart high-side switches that can also be configured as push-pull drivers for high-speed switching. The device is configured and controlled through the SPI interface. Care needs to be taken when selecting the output loads to ensure they do not exceed the 1A capability of the power adapter supplied. For higher currents, a different external 24V supply is required.

In the MAXREFDES200#, the MAX14912 is configured to operate in high-side mode and the outputs are connected in pairs (1-2, 3-4, 5-6, 7-8), giving four outputs providing higher current capabilities. This configuration still supports internal safe demagnetization when switching inductive loads and does not require external diodes to dissipate the stored energy.

Analog IO (AIO)

The Analog I/O is a single chip solution based on MAX22000, an industrial-grade universal analog input/output device that can be configured on-the-fly in software as a voltage output or input, or a current output or input. MAX22000 integrates an 18-bit DAC with fast settling time, a multi-channel 24-bit sigma-delta ADC, a precision voltage reference, programmable gain amplifiers (PGAs), and high voltage analog conditioning functions. The analog output can provide a voltage in the range of ±10V, provide a current in the range of ±20mA, measure a voltage in the range of ±10V, or measure a current in the range of ±20mA. A separate dedicated analog input measures a voltage in the range of ±10V. Another differential analog input has a dedicated PGA, offering ranges of ±10V, ±1.0V, ±500mV, ±250mV, or ±125mV. The selected input can be sampled from 1sps to 115.2ksps. MAX22000 is controlled using an SPI interface for all configuration and operation. The device requires low-voltage analog and digital supplies from 3V3_DIO and 3V3_AIO as well as high voltage ±24V supplies for the analog I/O from the HVDD and HVSS supplies.

Four types of MAX22000 analog IOs are used in MAXREFDES200#. IO pin AO1+ is a Universal Analog IO (UAIO), meaning it can be configured via software as an input (voltage or current mode) or as an output (voltage or current mode). AO1+ is capable of supporting input and output ranges of ±12.5V or ±25mA depending upon the software configuration – no hardware changes are required. This is accomplished using the MAX22000 pins for the DAC (AOP and AON), and ADC inputs (A1 and A2) for the Current Sense Amplifier (CSA) and ADC input (A3) for the voltage sense amplifier.

In addition to the UAIO port, other ADC inputs are brought out to the IO connectors on MAXREFDES215# with pin names for IO screw connectors J4 to J7 listed in Table 1. Inputs AI1+ and AI1- connects to ADC inputs A5 and A6 on the MAX22000. The Programmable Gain Amplifier (PGA) within MAX22000 can be set to different input voltage ranges, covering ±500mV, ±250mV, and ±125mV. Input AI2+ connects to ADC input AI4 with a voltage range of ±12.5V. Input AI3+ connects to ADC input AI1, note that in order to use this ADC voltage input, resistor R68 needs to be installed and UAIO mode is no longer available. AUX1 and AUX2 inputs on the MAX22000 are not used due to IO connector constraints. Refer to MAX22000 datasheet for full details of how to program the IC for different operating modes.

I/O Connector Port # MAXREFDES200 Signal MAXREFDES201 Signal
J4 IO_01+ DI_1 APP_M4B
  IO_01- GND APP_M2A
  IO_02+ DI_2 APP_M4A
  IO_02- GND APP_M2B
  IO_03+ DI_3 APP_M3B
  IO_03- GND APP_M1A
  IO_04+ DI_4 APP_M3A
  IO_04- GND APP_M1B
J5 IO_05+ DI_5 DI_1
  IO_05- GND GND
  IO_06+ DI_6 DI_2
  IO_06- GND GND
  IO_07+ DI_7 DI_3
  IO_07- GND GND
  IO_08+ DI_8 FLD_ENC1AP
  IO_08- GND FLD_ENC1AN
J6 IO_09+ DO_1 FLD_ENC1BP
  IO_09- GND FLD_ENC1BN
  IO_10+ DO_2 FLD_ENC1ZP
  IO_10- GND FLD_ENC1ZN
  IO_11+ DO_3 FLD_ENC2AP
  IO_11- GND FLD_ENC2AN
  IO_12+ DO_4 FLD_ENC2BP
  IO_12- GND FLD_ENC2BN
J7 IO_13+ AI1+ FLD_ENC3AP
  IO_13- AI1- FLD_ENC3AN
  IO_14+ AI2+ FLD_ENC3BP
  IO_14- GND FLD_ENC3BN
  IO_15+ AO1+ FLD_ENC4AP
  IO_15- GND FLD_ENC4AN
  IO_16+ AI3+ FLD_ENC4BP
  IO_16- GND FLD_ENC4BN

Table 1. J4 – J7 Connections for MAXREFDES200 and MAXREFDES201

Communication Ports
The MAXM22511 isolated RS-485/422 module with transceiver and power features a full-duplex isolated RS-485 interface. This full-duplex isolated RS-485/422 transceiver provides 2500VRMS of galvanic isolation between the cable-side (RS-485 driver/receiver side) and the UART side of the device. An integrated DC-DC powers the cable side of the module that requires no external components and removes the need for a separate field domain supply.

The MAXM22511 operates from a single 3.3V supply (3V3_DIO) and the integrated DC-DC converter generates the 3.3V operating voltage for the cable side of the module. The MAXM22511 connects to a MAX3108 UART and has a high ±15kV ESD performance and up to 25Mbps data rate.

UART
The MAXM22511 RS-485 transceiver TX and RX pins connect to a MAX3108 advanced universal asynchronous receiver-transmitter (UART), which has 128 words of receive and transmit first-in/first-out (FIFO) and connects using a high-speed SPI interface to the isolated field SPI bus and, thereafter, the application processor MCU.

IO Link Master
The MAXREFDES200# uses two MAX14819 dual-channel IO-Link master transceivers with a STM32F412 MCU that supports TMG's stack for implementing a 4-channel IO-Link master.

The MAX14819 low-power, dual-channel, IO-Link master transceiver with sensor/actuator power-supply controllers is fully compliant with the latest IO-Link and binary input standards and test specifications, IEC 61131-2, IEC 61131-9 SDCI, and IO-Link 1.1.2. This master transceiver also includes two auxiliary digital input (DI_) channels. The MAX14819 also features autonomous cycle timers, reducing the need for accurate controller timing. Integrated establish-communication sequencers also simplify wake-up management. The MAX14819 integrates two low-power sensor supply controllers with advanced current limiting, reverse current blocking, and reverse polarity protection capability to enable low-power robust solutions.

The 4-port IO-Link master uses TMG's IO-Link master stack, with the software running on a STM32F412 Arm Cortex-M4 microcontroller. Each of the two MAX14819 transceivers connect to a UART in the STM32F412 as well as through a local SPI bus for configuration. The MAXREFDES200# ships with the master stack preprogrammed inside with an indefinite time license.

For further information about TMG and their software, contact Technologie Management Gruppe, Technologie und Engineering GmbH:

Technologie Management Gruppe
Technologie und Engineering GmbH
Zur Gießerei 10
76227 Karlsruhe
Germany
Phone: +49721828060
Email: willems@tmgte.de
Web: www.tmgte.com

Detailed Description of the MAXREFDES201# Motion Control Module

Figure 8 shows the system block diagram for the MAXREFDES201#.


Figure 8. MAXREFDES201# block diagram.

Figure 9 shows the top view of the MAXREFDES201#.


Figure 9. MAXREFDES201# top view.

Connections
The MAXREFDES201# connects to the top side of the MAXREFDES215# through an 80-way male connector that mates with a female connector on the MAXREFDES215# carrier card. Both connectors are keyed to prevent incorrect insertion of the respective cards.

Galvanic Isolation
The Go-IO uses two different domains, which are separated using the Maxim digital isolator products. The field domain uses the 24V input supply and 24V GND for reference. The logic domain uses APP_PWR and APP_GND for reference and is found on the application processor card, MAXREFDES211#. Four Maxim digital isolators perform the galvanic isolation function on the MAXREFDES201# I/O control card. The MAX14130 (3 off) and MAX14483 isolate the SPI bus chip selects and other control signals (i.e., PWM, encoder lines). VDD_IO provides the logic domain power for the isolators and is generated using the integrated LDO within the MAX22192. 3V3_DIO provides field domain power for the isolators and is generated on the MAXREFDES201# card. The MAX22192 provides additional isolation and is an industrial octal digital input device with integrated isolation.

Power Supplies
Power is supplied to the MAXREFDES201# from the MAXREFDES215# (24V), and on-board regulators step down to provide the different voltage rails required by the I/O devices and digital isolators.

The MAXM15462 is a high-efficiency, synchronous step-down DC-DC module with integrated controller, MOSFETs, compensation components, and inductor that operates over a wide input-voltage range. The module operates from 4.5V to 42V input and delivers up to 300mA output current over a programmable output voltage from 0.9V to 5V. The module significantly reduces design complexity, manufacturing risks, and offers a true plug and play power/supply solution, reducing time-to-market.

One module generates a 3.3V output (3V3_DIO) used for powering the I/O interfaces and the field supply for the digital isolators. A second module generates a 5.0V output (5v0_DIO) used as one of the supplies for the MAX14890 encoders.

The MAX22192 has an integrated LDO which generates a 3.3V output from the 24V supply to provide the rail VDD_IO.

IO Interfaces
The MAXREFDES201# has a range of digital input and motor control interfaces as well as communication interfaces.

Digital Inputs
The MAX22192 is an IEC 61131-2 compliant industrial digital input device with integrated isolation. In the MAXREFDES211# three of the eight inputs are used to provide Type 1 or Type 3 interfaces. The MAX22192 has an isolated 4-pin SPI interface.

The MAX22192 isolates the APP_SPI2 bus and provides field domain signals to allow other field-side SPI devices to be shared with the MAX22192 and to share its isolation channels. In the MAXREFDES201#, the shared SPI bus is called FLD_SPI2 and connects to the encoder and UART devices. The MAX22192 is powered by a 24V field supply and generates a 3.3V output on the VDD3F pin from an integrated LDO regulator, which is used to power the MAX22192 and the field domain (VDD_IO) of the standalone digital isolators, MAX14430, and MAX14483.

DC Motor Drivers
The MAX14870 motor drivers provide a small, low-power and simple solution for driving and controlling the brushed DC motors and relays with voltages between 9V and 35V. Very low driver on-resistance reduces power dissipation. Input power for theses circuits is supplied by the green connector. In the MAXREFDES201#, four motor drivers are included, each supporting peak loads up to 2A. All motor driver control signals (i.e., EN, DIR, PWM) are connected to the application processor, MAXREFDES211#, through the digital isolators.

Encoders
The MAX14890E incremental encoder receiver contains four differential receivers and two single-ended receivers. The differential receivers can be operated in RS-422 or differential high-threshold logic (HTL) modes and are optionally configurable for single-ended TTL/HTL operation. The MAXREFDES201# uses three encoders. Each encoder has A, B, and Z differential inputs and an SPI interface that provides diagnostics and individual configurations for each receiver. The three MAX14890E encoders are daisy chained and connected to the isolated field domain SPI bus, FLD_SPI2.

Communication Ports
The MAXM22511 isolated RS-485/422 module with transceiver and power features a full-duplex isolated RS-485 interface. This full-duplex isolated RS-485/422 transceiver provides 2500VRMS of galvanic isolation between the cable-side (RS-485 driver/receiver side) and the UART side of the device. An integrated DC-DC powers the cable side of the module that requires no external components and removes the need for a separate field domain supply.

The MAXM22511 operates from a single 3.3V supply (3V3_DIO) and the integrated DC-DC converter generates the 3.3V operating voltage for the cable side of the module. The MAXM22511 connects to a MAX3108 UART and has a high ±15kV ESD performance and up to 25Mbps data rate.

UART
The MAXM22511 RS-485 transceiver TX and RX pins connect to a MAX3108 advanced universal asynchronous receiver-transmitter (UART), which has 128 words of receive and transmit first-in/first-out (FIFO) and connects using a high-speed SPI interface to the isolated field SPI bus and, thereafter, the application processor MCU.

Quick Start Guide

The Go-IO industrial IoT reference design can be used to control IO-Link, digital input (DI), digital output (DO), and RS-485 devices. This quick start guide shows how to get the system up and running to exercise these IO peripherals.

Required Equipment:
Maxim Supplied:

  • MAXREFDES200# Go-IO Factory Automation Board
  • MAXREFDES211# Application Processor Board
  • MAXREFDES215# Carrier Board
  • 24V 1A DC Wall Adapter

User supplied:

  • Windows® 7, Windows 8, Windows 10 PC with USB port
  • Micro USB 2.0 cable
  • Devices (IO-Link device, RS-485 device, DI device, DO device)
  • Cables to connect devices (M12 or wires)
  • Terminal program such as PuTTY
  • FTDI COM port drivers

Initial Setup Procedure

  1. Connect the MAXREFDES200# to the carrier board MAXREFDES215#.

    insert board connect 1

  2. Connect the MAXREFDES211# to the carrier board MAXREFDES215#.

    insert board connect 2

  3. Connect any other I/O devices to the respective I/O connectors.
  4. Power boards by connecting the 24V DC power adapter into an outlet and into the barrel connector on the MAXREFDES215# carrier board.
  5. Download and install the FTDI drivers for COM port functionality. Go to https://www.ftdichip.com/Drivers/CDM/CDM21228_Setup.zip.
    • Unzip the folder and double click the executable file to install the drivers.

      insert FTDI Install

  6. If not already installed, download a terminal program such as PuTTY.
  7. Connect the micro USB cable to the PC and to CN1 on the MAXREFDES211#.

    insert board usb

  8. When the device is powered and connected, open PuTTY and select "Session" in the left panel.
    • Select the connection type to "Serial."
    • In the "Speed" field, enter 115200.
    • In the "Serial line" field, enter the COM port "COMxxx," where xxx is replaced with the port number. To check the port number, open the Device Manager and unplug and re-plug to see which USB Serial Port disappears and reappears.

      insert PuTTY Session 1

  9. Select "Terminal" in the left panel.
    • Mark the check box for "Implicit CR in every LF."
    • For local echo, select the radio button "Force on."
    • For local line editing, select the radio button "Force on."

      insert PuTTY Terminal 1

  10. It is recommended to go back to "Session" in the left panel and save the session so that the settings can be easily reopened.
  11. Once saved, click "Open."
  12. If there is an empty terminal window, press "a" and "Enter" to display the main menu.

    insert GUI MainMenu

  13. Follow the terminal prompts to exercise the desired I/O.

Self-test Procedure
The self-test can help ensure that the Go-IO is operating as expected.

  1. Complete the Initial Setup Procedure.
  2. Remove power from the MAXREFDES215# before making new connections.
  3. To run the full self-test, connect the following on the MAXREFDES215#:
    • DO1 → DI1 (IO_09+ → IO_01+)
    • DO2 → DI3 (IO_10+ → IO_03+)
    • DO3 → DI5 (IO_11+ → IO_05+)
    • DO4 → DI7 (IO_12+ → IO_07+)
    • AI1+ -> AI1- (IO_13+ -> IO_13-)
    • AI2+ -> AO1+ (IO_14+ -> IO_15+)
    • Connect each of the four IO-Link ports to a MAXREFDES27# (not supplied) or four other user-supplied IO-Link sensors
  4. Reconnect power to the MAXREFDES215#.
  5. Connect the USB cable to the PC and CN1 of the MAXREFDES211#.

    insert board usb

  6. Open the PuTTY program and load the previously saved settings to connect.
  7. Press "a" and then press "Enter" to show the main menu.
  8. Press "1" and "Enter" to run the self-test.

    insert GUI_SelfTest

  9. The self-test program runs three tests for each IO-Link port.
    • Initial test establishes a connection.
      • If all connections are made, you should see 0 failure totals, and a final PASS result.
      • If all connections are not made, a connection error has occurred, and the module is unusable.
    • Vendor ID and device ID tests. The test program assumes the IO-Link sensor on each IO-Link port is the MAXREFDES27# and looks for the vendor ID and device ID. If an alternative sensor is used and a non-zero value is returned for each ID, the test does not provide a FAIL result.
  10. The user must manually check that the reported values for the vendor ID and device ID (reported in the GUI) are correct and match the values for the IO-Link sensor IODD file.
  11. The self-test program tests the analog ports. With AI1 shorted it should read 0V and AI2 should confirm the 3V generated by AO1.

1-Wire is a registered trademark of Maxim Integrated Products, Inc.
Arm is a registered trademark and registered service mark of Arm Limited.
Cortex is a registered trademark of Arm Limited.
IO-Link is a registered trademark of Profibus User Organization (PNO).
Maxim is a registered trademark of Maxim Integrated Products, Inc.
Maxim Integrated is a trademark of Maxim Integrated Products, Inc.
Wi-Fi is a registered certification mark of Wi-Fi Alliance Corporation.
Windows is a registered trademark and registered service mark of Microsoft Corporation.

Maxim Devices (18)

Part Number Name Product Family Order Design kits and evaluation modules
MAX22192 Octal Industrial Digital Input with Diagnostics and Digital Isolation Sensor Interface Buy Now Design Kits
MAX14912 Octal High-Speed, High-Side Switch/Push-Pull Driver MOSFET Drivers and Controllers Buy Now Design Kits
MAXM22511 2.5kVRMS Complete Isolated RS-485/RS-422 Module Transceiver + Power Transceivers Buy Now Design Kits
MAX14819 Dual IO-Link Master Transceiver with Integrated Framers and L+ Supply Controllers Sensor Interface Buy Now Design Kits
MAX14483 6-Channel, Low-Power, 3.75kVRMS SPI Digital Isolator Isolation Buy Now Design Kits
MAX14130 4-Channel, 1kVRMS, 2.75kVRMS, and 3.75kVRMS Digital Isolators Isolation Buy Now Design Kits
MAX14870 Compact 4.5V to 36V Full-Bridge DC Motor Drivers Motor Driver ICs Buy Now Design Kits
MAX14890E Incremental Encoder Interface for RS-422, HTL, and TTL with Digital Inputs Transceivers Buy Now Design Kits
MAX32630 Ultra-Low-Power Arm Cortex-M4 with FPU-Based Microcontroller (MCU) with 2MB Flash and 512KB SRAM MCU - Microcontroller Buy Now Design Kits
MAX17502 60V, 1A, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter Switching Regulators Buy Now Design Kits
MAXM15462 4.5V to 42V, 300mA Himalaya uSLIC Step-Down Power Module Switching Regulators Buy Now Design Kits
MAX17681 4.5V to 42V Input, High-Efficiency, Iso-Buck DC-DC Converter Isolated Power Buy Now Design Kits
MAX1806 500mA, Low-Voltage Linear Regulator in µMAX Linear Regulators (LDOs) Buy Now Not Available
MAX17608 4.5V to 60V, 1A Current Limiter with OV, UV, and Reverse Protection Complete System Power Protection IC Buy Now Design Kits
MAX15062 60V, 300mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converters Switching Regulators Buy Now Design Kits
MAX3108 SPI/I²C UART with 128-Word FIFOs in WLP Controllers/Expanders Buy Now Not Available
MAX14430 Four-Channel, Fast, Low-Power, 3kVRMS and 3.75kVRMS Digital Isolators Isolation Buy Now Design Kits
MAX22000 Industrial Configurable Analog I/O Digital-to-Analog Converters Buy Now Design Kits

Maxim Devices (18)

Part Number Product Family
Sensor Interface
Octal Industrial Digital Input with Diagnostics and Digital Isolation
MOSFET Drivers and Controllers
Octal High-Speed, High-Side Switch/Push-Pull Driver
Transceivers
2.5kVRMS Complete Isolated RS-485/RS-422 Module Transceiver + Power
Sensor Interface
Dual IO-Link Master Transceiver with Integrated Framers and L+ Supply Controllers
Isolation
6-Channel, Low-Power, 3.75kVRMS SPI Digital Isolator
Isolation
4-Channel, 1kVRMS, 2.75kVRMS, and 3.75kVRMS Digital Isolators
Motor Driver ICs
Compact 4.5V to 36V Full-Bridge DC Motor Drivers
Transceivers
Incremental Encoder Interface for RS-422, HTL, and TTL with Digital Inputs
MCU - Microcontroller
Ultra-Low-Power Arm Cortex-M4 with FPU-Based Microcontroller (MCU) with 2MB Flash and 512KB SRAM
Switching Regulators
60V, 1A, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter
Switching Regulators
4.5V to 42V, 300mA Himalaya uSLIC Step-Down Power Module
Isolated Power
4.5V to 42V Input, High-Efficiency, Iso-Buck DC-DC Converter
Linear Regulators (LDOs)
500mA, Low-Voltage Linear Regulator in µMAX
Not Available
Complete System Power Protection IC
4.5V to 60V, 1A Current Limiter with OV, UV, and Reverse Protection
Switching Regulators
60V, 300mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converters
Controllers/Expanders
SPI/I²C UART with 128-Word FIFOs in WLP
Not Available
Isolation
Four-Channel, Fast, Low-Power, 3kVRMS and 3.75kVRMS Digital Isolators
Digital-to-Analog Converters
Industrial Configurable Analog I/O

Design Files (21)

Title Type Size Date
marketing_bom_maxrefdes200_apps_b PDF 51KB 2020-10-15
maxrefdes200_apps_a_fab_assembly ZIP 9MB 2020-10-15
build_bom_maxrefdes201_apps_a PDF 112KB 2018-11-02
maxrefdes201_apps_a_fab_assembly ZIP 7MB 2019-07-09
build_bom_maxrefdes211_apps_a PDF 125KB 2019-07-09
maxrefdes211_apps_a_fab_assembly ZIP 7MB 2019-07-09
build_bom_maxrefdes215_apps_a PDF 108KB 2019-07-09
maxrefdes215_apps_a_fab_assembly ZIP 5MB 2019-07-09
maxrefdes201_apps_a_marketing_sch PDF 223KB 2019-07-09
maxrefdes211_hardware_files ZIP 11MB 2019-07-09
maxrefdes215_hardware_files ZIP 9MB 2019-07-09
maxrefdes211_apps_a_marketing_sch PDF 54KB 2019-07-09
maxrefdes201_apps_a_marketing_pcb PDF 4MB 2019-07-09
maxrefdes200_apps_a_marketing_sch PDF 285KB 2020-10-15
maxrefdes200_all_design_files ZIP 47MB 2019-07-09
maxrefdes215_apps_a_marketing_sch PDF 414KB 2019-07-09
maxrefdes200_apps_a_marketing_pcb PDF 6MB 2020-10-15
maxrefdes201_hardware_files ZIP 11MB 2019-07-09
maxrefdes200_hardware_files ZIP 15MB 2020-10-15
maxrefdes211_apps_a_marketing_pcb PDF 4MB 2019-07-09
maxrefdes215_apps_a_marketing_pcb PDF 3MB 2019-07-09
Date Type
2020-10-15

marketing_bom_maxrefdes200_apps_b

(PDF, 51KB)

2020-10-15

maxrefdes200_apps_a_fab_assembly

(ZIP, 9MB)

2018-11-02

build_bom_maxrefdes201_apps_a

(PDF, 112KB)

2019-07-09

maxrefdes201_apps_a_fab_assembly

(ZIP, 7MB)

2019-07-09

build_bom_maxrefdes211_apps_a

(PDF, 125KB)

2019-07-09

maxrefdes211_apps_a_fab_assembly

(ZIP, 7MB)

2019-07-09

build_bom_maxrefdes215_apps_a

(PDF, 108KB)

2019-07-09

maxrefdes215_apps_a_fab_assembly

(ZIP, 5MB)

2019-07-09

maxrefdes201_apps_a_marketing_sch

(PDF, 223KB)

2019-07-09

maxrefdes211_hardware_files

(ZIP, 11MB)

2019-07-09

maxrefdes215_hardware_files

(ZIP, 9MB)

2019-07-09

maxrefdes211_apps_a_marketing_sch

(PDF, 54KB)

2019-07-09

maxrefdes201_apps_a_marketing_pcb

(PDF, 4MB)

2020-10-15

maxrefdes200_apps_a_marketing_sch

(PDF, 285KB)

2019-07-09

maxrefdes200_all_design_files

(ZIP, 47MB)

2019-07-09

maxrefdes215_apps_a_marketing_sch

(PDF, 414KB)

2020-10-15

maxrefdes200_apps_a_marketing_pcb

(PDF, 6MB)

2019-07-09

maxrefdes201_hardware_files

(ZIP, 11MB)

2020-10-15

maxrefdes200_hardware_files

(ZIP, 15MB)

2019-07-09

maxrefdes211_apps_a_marketing_pcb

(PDF, 4MB)

2019-07-09

maxrefdes215_apps_a_marketing_pcb

(PDF, 3MB)

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