SBOS375D October   2006  – October 2024 XTR111

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configurations and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Explanation of Pin Functions
      2. 6.3.2 Dynamic Performance
      3. 6.3.3 External Current Limit
      4. 6.3.4 External MOSFET
      5. 6.3.5 Output Error Flag and Disable Input
      6. 6.3.6 Voltage Regulator
      7. 6.3.7 Level Shift of 0V Input and Transconductance Trim
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Input Voltage
      2. 7.1.2 Error Flag Delay
      3. 7.1.3 Voltage Output Configuration
      4. 7.1.4 4mA-to-20mA Output
    2. 7.2 Typical Applications
      1. 7.2.1 0mA–20mA Voltage-to-Current Converter
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
        3. 7.2.1.3 Application Curve
      2. 7.2.2 Additional Applications
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
        1. 7.4.1.1 Package and Heat Dissipation
        2. 7.4.1.2 Thermal Pad Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Third-Party Products Disclaimer
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DRC|10
  • DGQ|10
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6.1 Overview

The XTR111 is a voltage-controlled current source capable of delivering currents from 0mA to 32mA. The primary intent of the XTR111 is to source the commonly-used industrial current ranges of 0mA to 20mA or 4mA to 20mA. The performance is specified for a supply voltage of up to 40V. The maximum supply voltage is 44V. The voltage-to-current ratio is defined by an external resistor, RSET; therefore, the input voltage range can be freely set in accordance with application requirements. The output current is cascoded by an external P-channel MOSFET transistor for large voltage compliance extending below ground, and for easy power dissipation. This arrangement provides excellent suppression of typical interference signals from the industrial environment because of the extremely high output impedance and wide voltage compliance.

An error detection circuit activates a logic output (error flag pin, EF) in case the output current cannot correctly flow. The EF pin indicates a wire break, high load resistor, or loss of headroom for the current output to the positive supply. The output disable (OD) pin provided can be used during power-on, multiplexing, and other conditions where the output presents no current. The OD pin has an internal pullup that causes the XTR111 to come up in output disable mode unless the OD pin is tied low.

The onboard voltage regulator can be adjusted from 3V to 15V and delivers up to 5mA load current. The voltage regulator is intended to supply signal conditioning and sensor excitation in 3-wire sensor systems. Voltages greater than 3V can be set by a resistive divider.

Figure 6-1 shows the basic connections. Input voltage VVIN reappears across RSET and controls 1/10 of the output current. The I-Mirror has a precise current gain of 10. This configuration has a transfer function of:

Equation 1. I O U T = 10   × V V I N R S E T

Set the voltage regulator output to a range of 3V to 12V by selecting R1 and R2 using the following equation:

Equation 2. V R E G F = 3V × ( R 1 + R 2 ) R 2
XTR111 Basic Connection for 0mA to 20mA Related to a 0V-to-5V Signal Input With the Voltage Regulator Set to a 5V Output Figure 6-1 Basic Connection for 0mA to 20mA Related to a 0V-to-5V Signal Input With the Voltage Regulator Set to a 5V Output