Manuali utente per Texas Instruments XTR108 Evaluation Module USB Version XTR108EVM-USB

Sommario

• XTR108EVM-USB Evaluation Board and Software Tutorial

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  • 1 Overview

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    • 1.1 XTR108EVM-USB Kit Contents

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    • 1.2 Related Documentation from Texas Instruments

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  • 2 Hardware Overview

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    • 2.1 XTR108EVM-USB Theory of Operation

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    • 2.2 Interface Board Overview

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      • 2.2.1 Interface Board: Signal Definitions and Pinouts

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        • 2.2.1.1 Multimeter Connect

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        • 2.2.1.2 J1 (15-Pin Female DSUB)

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        • 2.2.1.3 J2 (Vo_XTR108)

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        • 2.2.1.4 J3 (Io_XTR108)

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        • 2.2.1.5 J4 (Loop Supply)

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        • 2.2.1.6 J5 (25-Pin Female DSUB)

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        • 2.2.1.7 J6 (25-Pin Male DSUB)

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        • 2.2.1.8 J7 (SPI)

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        • 2.2.1.9 J8 (RTD_CON)

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      • 2.2.2 Interface Board Jumper Settings

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    • 2.3 Sensor Board Overview

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      • 2.3.1 Sensor Board Connections

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        • 2.3.1.1 J1 (SPI)

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        • 2.3.1.2 J2 (15-pin Male DSUB)

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        • 2.3.1.3 J3 (Io_XTR108)

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        • 2.3.1.4 J4 (Vo_XTR108)

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        • 2.3.1.5 J5 (RTD_CON)

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      • 2.3.2 Sensor Board Jumper Settings

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      • 2.3.3 Test Points and Miscellaneous Breadboard Area

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  • 3 Hardware Setup

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    • 3.1 Electrostatic Discharge Warning

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    • 3.2 Connecting the Hardware

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    • 3.3 Connecting Power and USB to the USB DAQ Platform

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    • 3.4 Connecting Loop Power Supply to the XTR108EVM-USB Interface Board

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    • 3.5 Connecting Outputs to a Digital Multimeter (DMM)

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    • 3.6 USB DAQ Platform Default Jumper Settings

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    • 3.7 XTR108EVM-USB Interface Board Default Jumper Settings

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    • 3.8 XTR108EVM-USB Sensor Board Default Jumper Settings

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  • 4 Software Setup

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    • 4.1 Operating Systems for XTR108EVM-USB Software

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    • 4.2 XTR108EVM-USB Software Installation

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    • 4.3 Starting the XTR108EVM-USB Software

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  • 5 Software Overview

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    • 5.1 Block Diagram Tab

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      • 5.1.1 Input MUX

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      • 5.1.2 PGA

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      • 5.1.3 I_ZERO DAC

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      • 5.1.4 I_REF DAC

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      • 5.1.5 I_LIN DAC

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      • 5.1.6 Overscale/Underscale

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      • 5.1.7 SPI Interface

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      • 5.1.8 Alarm Config

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    • 5.2 Find Resistors Tab

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      • 5.2.1 Step 1: Enter Operating Conditions

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        • 5.2.1.1 Mode

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        • 5.2.1.2 Output Span

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        • 5.2.1.3 Overscale and Underscale

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        • 5.2.1.4 Channel Enable

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        • 5.2.1.5 Temperature

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        • 5.2.1.6 RTD Type

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        • 5.2.1.7 CVD Coefficients

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      • 5.2.2 Step 2: Calculate Resistor Values

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      • 5.2.3 Step 3: Install These Resistors

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      • 5.2.4 Step 4: Save or Load Model File

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    • 5.3 Manual Calibration Tab

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      • 5.3.1 Step 1: Initialize

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      • 5.3.2 Step 2: Set RTD Emulator

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      • 5.3.3 Step 3: First Corrections

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      • 5.3.4 Step 4: Second Corrections

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      • 5.3.5 Step 5: Error Calculator

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      • 5.3.6 Step 6: Underscale and Overscale Calibration

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      • 5.3.7 Verify Calibration

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      • 5.3.8 Reset Calibration

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    • 5.4 Automatic Calibration Tab

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      • 5.4.1 DMM Connection

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      • 5.4.2 Step 1: Load Model File

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      • 5.4.3 Step 2: Select Channel

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      • 5.4.4 Step 3: Set RTD Emulator

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      • 5.4.5 Step 4: Initiate Auto-Cal

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      • 5.4.6 Verify Calibration

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    • 5.5 Registers Tab

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      • 5.5.1 Register and EEPROM Communications

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      • 5.5.2 Save/Load Register Settings

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      • 5.5.3 Register Table and Register Bits

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    • 5.6 Tools Menu

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      • 5.6.1 Control Bits

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      • 5.6.2 Debug Window

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      • 5.6.3 About Window

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  • 6 General Operating Tips

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    • 6.1 Voltage Output Mode

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    • 6.2 Charge Pump

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  • 7 Hardware Documentation

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    • 7.1 Schematics

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    • 7.2 Layouts

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    • 7.3 Bill of Materials (BOM)

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  • 8 Appendix

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    • 8.1 XTR108 Operation

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      • 8.1.1 Input MUX

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      • 8.1.2 RSET

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      • 8.1.3 RLIN

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      • 8.1.4 Linearity Correction

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    • 8.2 XTR108 Calibration Equations (Current-Output Mode)

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      • 8.2.1 Initial Calculations

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        • 8.2.1.1 RTD Resistance

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        • 8.2.1.2 Relative Nonlinearity

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        • 8.2.1.3 Linearization Coefficient

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        • 8.2.1.4 IREF DAC (Excitation Current Source)

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        • 8.2.1.5 IZERO DAC (Zero Offset)

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        • 8.2.1.6 Calculate DAC Codes

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      • 8.2.2 First Corrections

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        • 8.2.2.1 Linearization Register

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        • 8.2.2.2 IREF Registers

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        • 8.2.2.3 IZERO Registers

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      • 8.2.3 Second Corrections

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        • 8.2.3.1 Linearization Register

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    • 8.3 XTR108 Calibration Equations (Voltage-Output Mode)

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    • 8.4 Mnemonic Commands

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• Important Notices

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