SBOS092B June   1998  – January 2025 XTR106

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 Recommended Operating Conditions
    3. 5.3 Thermal Information
    4. 5.4 Electrical Characteristics
    5. 5.5 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 Linearization
      2. 6.3.2 Reverse-Voltage Protection
      3. 6.3.3 Overvoltage Surge Protection
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 External Transistor
      2. 7.1.2 Loop Power Supply
      3. 7.1.3 Bridge Balance
      4. 7.1.4 Underscale Current
      5. 7.1.5 Low-Impedance Bridges
      6. 7.1.6 Other Sensor Types
      7. 7.1.7 Radio Frequency Interference
      8. 7.1.8 Error Analysis
    2. 7.2 Typical Applications
    3. 7.3 Layout
    4. 7.4 Layout Guidelines
  9. 8 Device and Documentation Support
    1. 8.1 Documentation Support
    2. 8.2 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

7.1.2 Loop Power Supply

The voltage applied to the XTR106, V+, is measured with respect to the IO connection, pin 7. V+ can range from 7.5V to 36V. The loop-supply voltage, VPS, differs from the voltage applied to the XTR106 according to the voltage drop on the current sensing resistor, RL (plus any other voltage drop in the line).

If a low loop-supply voltage is used, RL (including the loop wiring resistance) must be made a relatively low value so that V+ remains 7.5V or greater for the maximum loop current of 20mA:

Equation 10. RL MAX=V+-7.5V20mA-RWIRING

For loop currents up to 30mA, design for V+ equal or greater than 7.5V to allow for out-of-range input conditions. V+ must be at least 8V if 5V sensor excitation is used and if correcting for bridge nonlinearity greater than +3%.

The low operating voltage (7.5V) of the XTR106 allows operation directly from personal computer power supplies (12V ±5%). When used with the RCV420 Current Loop Receiver (Figure 7-6), load resistor voltage drop is limited to 3V.