Circuit Note

CN-0575

analog.com

Circuits from the Lab™ circuits from Analog Devices have been designed and built by Analog Devices

engineers. Standard engineering practices have been employed in the design and construction of each circuit,

and their function and performance have been tested and verified in a lab environment at room temperature.

However, you are solely responsible for testing the circuit and determining its suitability and applicability for

your use and application. Accordingly, in no event shall Analog Devices be liable for direct, indirect, special,

incidental, consequential or punitive damages due to any cause whatsoever connected to the use of any

Circuits from the Lab circuits. (Continued on last page)

Rev. 0 | 1 of 7

Circuits from the Lab

® reference designs are engi-

neered and tested for quick and easy system integra-

tion to help solve today’s analog, mixed-signal, and

RF design challenges. For more information and/or

support, visit www.analog.com/CN0575.

Devices Connected/Referenced

ADIN1110

Robust Industrial, Low Power 10BASE-T1L Ethernet MAC-PHY

LTC9111

Industrial SPoE PD Controller

LT8304

100 VIN Micropower No-Opto Isolated Flyback Converter with 150 V/

2 A Switch

ADT75

±1°C Accurate, 12-Bit Digital Temperature Sensor

10BASE-T1L Field Device Development Platform with Class 12 and 13 SPoE

EVALUATION AND DESIGN SUPPORT

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Circuit Evaluation Boards

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CN0575 Circuit Evaluation Board (EVAL-CN0575-RPIZ)

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Design and Integration Files

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Schematics, Layout Files, Bill of Materials

CIRCUIT FUNCTIONS AND BENEFITS

10BASE-T1L is an Ethernet physical layer standard (IEEE

802.3cg-2019) that is dramatically changing the process and factory

automation industry by providing seamless Ethernet connectivity to

field-level devices including machines, controls, indicators, sensors,

and actuators. 10BASE-T1L improves on existing standards such

as 4 mA to 20 mA, HART, and FieldBus. Similar to conventional

process automation networks, 10BASE-T1L allows both data and

DC power to be transmitted over a single twisted pair via single-pair

power over Ethernet (SPoE) or Ethernet advanced physical layer

(APL).

Compared to traditional methods, 10BASE-T1L offers higher power

delivery, higher bandwidth, longer transmission distances, lower-

cost cabling in new installations, and reuse of 4 mA to 20 mA

and RS485 wiring when retrofitting legacy installations. Ethernet

supports PROFINET®, EtherCAT/IP, HART/IP, OPC UA™, Mod-

bus®/TCP, and IoT protocols such as message queuing telemetry

transport (MQTT). Ethernet also enables simple, centrally controlled

software updates right down to the end nodes, which enables faster

network commissioning and maintenance.

The circuit shown in Figure 1 is a 10BASE-T1L MAC/PHY interface

with SPoE for development of field devices and applications on a

Raspberry Pi platform board. The SPoE powered device (PD) and

isolated flyback regulator provide 5 V power to the platform board

and attached application circuitry. SPoE Class 12 (8.4 W, 24 V

nominal) and Class 13 (7.7 W, 55 V nominal) are supported.

The MAC/PHY interfaces to the platform board via serial peripheral

interface (SPI), allowing it to be used with microcontrollers and

processors that lack an integrated media access control (MAC)

layer. The circuit includes a digital temperature sensor, LEDs,

and push button, which implement a basic field device example

application. The example field device’s drivers are in the Linux in-

dustrial input/output (IIO) subsystem, providing a host of debug and

development utilities, and cross-platform application programming

interface (API) with Python, C, C#, and MATLAB

® support.

Figure 1. CN0575 Simplified Block Diagram