SLOS877C October   2014  – April 2021 TMP451-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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 Characteristics for Figure 1-1
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Temperature Measurement Data
        1. 7.3.1.1 Standard Binary to Decimal Temperature Data Calculation Example
        2. 7.3.1.2 Standard Decimal to Binary Temperature Data Calculation Example
      2. 7.3.2 Series Resistance Cancellation
      3. 7.3.3 Differential Input Capacitance
      4. 7.3.4 Filtering
      5. 7.3.5 Sensor Fault
      6. 7.3.6 ALERT and THERM Functions
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode (SD)
    5. 7.5 Programming
      1. 7.5.1 Serial Interface
        1. 7.5.1.1 Bus Overview
        2. 7.5.1.2 Bus Definitions
        3. 7.5.1.3 Serial Bus Address
        4. 7.5.1.4 Read and Write Operations
        5. 7.5.1.5 Timeout Function
        6. 7.5.1.6 High-Speed Mode
    6. 7.6 Register Map
      1. 7.6.1 Register Information
        1. 7.6.1.1  Pointer Register
        2. 7.6.1.2  Temperature Registers
        3. 7.6.1.3  Status Register
        4. 7.6.1.4  Configuration Register
        5. 7.6.1.5  Conversion Rate Register
        6. 7.6.1.6  One-Shot Start Register
        7. 7.6.1.7  η-Factor Correction Register
        8. 7.6.1.8  Offset Register
        9. 7.6.1.9  General Call Reset
        10. 7.6.1.10 Identification Register
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.6.1.7 η-Factor Correction Register

The TMP451-Q1 device allows for a different η-factor value to be used for converting remote channel measurements to temperature. The remote channel uses sequential current excitation to extract a differential VBE voltage measurement to determine the temperature of the remote transistor. Equation 1 shows this voltage and temperature.

Equation 1. GUID-FB44C0F6-6044-4C6C-9E24-BACF5C7644FB-low.gif

The value η in Equation 1 is a characteristic of the particular transistor used for the remote channel. The power-on reset value for the TMP451-Q1 device is η = 1.008. The value in the η-factor correction register may be used to adjust the effective η-factor according to Equation 2 and Equation 3.

Equation 2. GUID-1F3E55C0-7F00-4E38-BC32-1A7C5F104F80-low.gif
Equation 3. GUID-A3A2B5B7-8348-4C4C-B3C8-E9C28B040D2E-low.gif

The η-factor correction value must be stored in twos complement format, yielding an effective data range from –128 to 127. The η-factor correction value is written to and read from pointer address 23h. The register power-on reset value is 00h, thus having no effect unless a different value is written to it.

Table 7-8 η-Factor Range
NADJUSTη
BINARYHEXDECIMAL
0111 11117F1270.950198
0000 10100A101.003195
0000 10000881.004152
0000 01100661.005111
0000 01000441.006072
0000 00100221.007035
0000 00010111.007517
0000 00000001.008
1111 1111FF–11.008483
1111 1110FE–21.008967
1111 1100FC–41.009935
1111 1010FA–61.010905
1111 1000F8–81.011877
1111 0110F6–101.012851
1000 000080–1281.073837