SBOS441I September   2009  – October 2019 TMP431 , TMP432

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Typical Application Schematics
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Temperature Measurement Data
      2. 8.3.2 Beta Compensation
      3. 8.3.3 Series Resistance Cancellation
      4. 8.3.4 Differential Input Capacitance
      5. 8.3.5 Filtering
      6. 8.3.6 Sensor Fault
      7. 8.3.7 THERM and ALERT/THERM2
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown Mode (SD)
      2. 8.4.2 One-Shot Mode
    5. 8.5 Programming
      1. 8.5.1  Serial Interface
      2. 8.5.2  Bus Overview
      3. 8.5.3  Timing Diagrams
      4. 8.5.4  Serial Bus Address
      5. 8.5.5  Read and Write Operations
      6. 8.5.6  Undervoltage Lockout
      7. 8.5.7  Timeout Function
      8. 8.5.8  High-Speed Mode
      9. 8.5.9  General Call Reset
      10. 8.5.10 SMBus Alert Function
    6. 8.6 Register Maps
      1. 8.6.1  Pointer Register
      2. 8.6.2  Temperature Registers
      3. 8.6.3  Limit Registers
      4. 8.6.4  Status Registers
        1. 8.6.4.1 TMP431 Status Register
        2. 8.6.4.2 TMP432 Status Register
      5. 8.6.5  Configuration Register 1
      6. 8.6.6  Configuration Register 2
      7. 8.6.7  Conversion Rate Register
      8. 8.6.8  Beta Compensation Configuration Register
      9. 8.6.9  η-Factor Correction Register
      10. 8.6.10 Software Reset
      11. 8.6.11 Consecutive Alert Register
      12. 8.6.12 Therm Hysteresis Register
      13. 8.6.13 Identification Registers
      14. 8.6.14 Open Status Register
      15. 8.6.15 Channel Mask Register
      16. 8.6.16 High Limit Status Register
      17. 8.6.17 Low Limit Status Register
      18. 8.6.18 THERM Limit Status Register
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Examples
  12. 12Device and Documentation Support
    1. 12.1 Related Links
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

11.1 Layout Guidelines

Remote temperature sensing on the TMP43x measures very small voltages using very low currents; therefore, noise at the IC inputs must be minimized. Most applications using the TMP43x have high digital content, with several clocks and logic level transitions creating a noisy environment. Layout must conform to the following guidelines:

  1. Place the TMP43x as close to the remote junction sensor as possible.
  2. Route the DXP and DXN traces next to each other and shield them from adjacent signals through the use of ground guard traces; see Figure 25. If a multilayer PCB is used, bury these traces between ground or VDD planes to shield them from extrinsic noise sources. TI recommends 5 mil (0.127 mm) PCB traces.
  3. Minimize additional thermocouple junctions caused by copper-to-solder connections. If these junctions are used, make the same number and approximate locations of copper-to-solder connections in both the DXP and DXN connections to cancel any thermocouple effects.
  4. Use a 0.1-μF local bypass capacitor directly between the V+ and GND of the TMP43x. Figure 26 illustrates the suggested bypass capacitor placement for the TMP43x. This capacitance includes any cable capacitance between the remote temperature sensor and TMP43x.
  5. If the connection between the remote temperature sensor and the TMP43x is less than 8 inches
    (20.32 cm), use a twisted-wire pair connection. Beyond 8 inches, use a twisted, shielded pair with the shield grounded as close to the TMP43x as possible. Leave the remote sensor connection end of the shield wire open to avoid ground loops and 60-Hz pickup.
  6. Thoroughly clean and remove all flux residue in and around the pins of the TMP43x to avoid temperature offset readings as a result of leakage paths between DXP or DXN and GND, or between DXP or DXN and V+.