• Menu
  • Product
  • Email
  • PDF
  • Order now

  • HART-Enabled Transmitter Based on an Evaluation Module Design

    • SLAAER4 March   2025 AFE781H1 , AFE782H1 , AFE881H1 , AFE882H1 , DAC8740H , DAC8741H , DAC8742H

       

  • CONTENTS
  • SEARCH
  • HART-Enabled Transmitter Based on an Evaluation Module Design
  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 The 4-20mA Loop
    2. 1.2 The HART Protocol
      1. 1.2.1 Adding HART to the 4-20mA Loop
      2. 1.2.2 HART FSK
  5. 2AFE882H1 EVM-Based HART Transmitter
    1. 2.1 AFE882H1 HART Modem
    2. 2.2 AFE882H1 Evaluation Module
    3. 2.3 HART Transmitter Construction
      1. 2.3.1 Detailed Schematic
        1. 2.3.1.1 Input Protection
        2. 2.3.1.2 Start Up With Low-Dropout Regulator
        3. 2.3.1.3 Voltage-to-Current Stage
        4. 2.3.1.4 Voltage-to-Current Calculation
        5. 2.3.1.5 HART Signal Transmission
        6. 2.3.1.6 HART Input Protection
        7. 2.3.1.7 HART Transmitter Board
        8. 2.3.1.8 Current Consumption
      2. 2.3.2 HART Protocol Stack
  6. 3HART Testing and Registration
    1. 3.1  HART History and the FieldComm Group
    2. 3.2  HART Testing Overview
      1. 3.2.1 HART Protocol Specifications
      2. 3.2.2 HART Protocol Test Specifications
      3. 3.2.3 Field Transmitter Device Testing
    3. 3.3  HART Test Equipment
    4. 3.4  HART Physical Layer Testing
      1. 3.4.1 FSK Sinusoid Test
      2. 3.4.2 Carrier Start and Stop Time Tests
      3. 3.4.3 Carrier Start and Stop Transient Tests
      4. 3.4.4 Output Noise During Silence
      5. 3.4.5 Analog Rate of Change Test
      6. 3.4.6 Receive Impedance Test
      7. 3.4.7 Noise Sensitivity Test
      8. 3.4.8 Carrier Detect Test
    5. 3.5  Data Link Layer Tests
      1. 3.5.1 Data Link Layer Test Specifications
      2. 3.5.2 Data Link Layer Test Logs
    6. 3.6  Universal Command Tests
    7. 3.7  Common-Practice Command Tests
    8. 3.8  Device Specific Command Tests
    9. 3.9  HART Protocol Test Submission
    10. 3.10 HART Registration
  7. 4Summary
  8. 5Acknowledgments
  9. 6References
  10. IMPORTANT NOTICE
search No matches found.
  • Full reading width
    • Full reading width
    • Comfortable reading width
    • Expanded reading width
  • Card for each section
  • Card with all content

 

Application Note

HART-Enabled Transmitter Based on an Evaluation Module Design

Abstract

This application note describes using the AFE882H1 in an evaluation module (EVM) to construct a HART®-enabled field transmitter for 4-20mA loop instrumentation. HART (Highway Addressable Remote Transducer) enables two-way digital communication across the current loop at the same time as transmitting the value of a primary process variable. First, a brief introduction to 4-20mA loops and the HART protocol is presented. The AFE882H1 is then introduced as an ultra-low-power, 16-bit digital-to-analog converter (DAC) combined with a HART modem. This device also has an on-board analog-to-digital converter (ADC) and integrated diagnostic sensors for system monitoring. The EVM used for this device is set up as a loop transmitter that sets the current in a 4-20mA loop. This EVM is coupled with a digital back-end board that connects with an MSP-EXP430FR5969 LaunchPad™ as the controller for the HART communications. Testing for this transmitter for HART registration is also presented. The physical layer test results for the waveform are described and the data link layer (DLL) test results for the HART signaling and timing are described. Application layer tests for HART universal commands (UAL) and commonly-implemented commands (CAL) are also described.

Trademarks

LaunchPad™ is a trademark of Texas Instruments.

HART® is a registered trademark of FieldComm Group, Inc.

Linux® is a registered trademark of Linus Torvalds.

All trademarks are the property of their respective owners.

1 Introduction

 
Texas Instruments

© Copyright 1995-2025 Texas Instruments Incorporated. All rights reserved.
Submit documentation feedback | IMPORTANT NOTICE | Trademarks | Privacy policy | Cookie policy | Terms of use | Terms of sale