SNOSD82D June   2018  – September 2022 TMP117

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 Switching Characteristics
    7. 6.7 Two-Wire Interface Timing
    8. 6.8 Timing Diagram
    9. 6.9 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 Power Up
      2. 7.3.2 Averaging
      3. 7.3.3 Temperature Result and Limits
    4. 7.4 Device Functional Modes
      1. 7.4.1 Continuous Conversion Mode
      2. 7.4.2 Shutdown Mode (SD)
      3. 7.4.3 One-Shot Mode (OS)
      4. 7.4.4 Therm and Alert Modes
        1. 7.4.4.1 Alert Mode
        2. 7.4.4.2 Therm Mode
    5. 7.5 Programming
      1. 7.5.1 EEPROM Programming
        1. 7.5.1.1 EEPROM Overview
        2. 7.5.1.2 Programming the EEPROM
      2. 7.5.2 Pointer Register
      3. 7.5.3 I2C and SMBus Interface
        1. 7.5.3.1 Serial Interface
          1. 7.5.3.1.1 Bus Overview
          2. 7.5.3.1.2 Serial Bus Address
          3. 7.5.3.1.3 Writing and Reading Operation
          4. 7.5.3.1.4 Slave Mode Operations
            1. 7.5.3.1.4.1 Slave Receiver Mode
            2. 7.5.3.1.4.2 Slave Transmitter Mode
          5. 7.5.3.1.5 SMBus Alert Function
          6. 7.5.3.1.6 General-Call Reset Function
          7. 7.5.3.1.7 Timeout Function
          8. 7.5.3.1.8 Timing Diagrams
    6. 7.6 Register Map
  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
        1. 8.2.2.1 Noise and Averaging
        2. 8.2.2.2 Self-Heating Effect (SHE)
        3. 8.2.2.3 Synchronized Temperature Measurements
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

7.3.2 Averaging

Users can configure the device to report the average of multiple temperature conversions with the AVG[1:0] bits to reduce noise in the conversion results. When the TMP117 is configured to perform averaging with AVG set to 01, the device executes the configured number of conversions to eight. The device accumulates those conversion results and reports the average of all the collected results at the end of the process. As shown in the noise histograms of Figure 6-6 and Figure 6-7, the temperature result output has a repeatability of approximately ±3 LSBs when there is no averaging and ±1 LSB when the device is configured to perform eight averages.

Figure 7-2 shows the total conversion cycle time trade-off when using the averaging mode to achieve this improvement in noise performance. Averaging will increase the average active current consumption due to increasing the active conversion time in a conversion cycle. For example a single active conversion typically takes 15.5 ms, so if the device is configured to report an average of eight conversions, then the active conversion time is 124 ms (15.5 ms × 8). Use Equation 1 to factor in this increase in active conversion time to accurately calculate the average current consumption of the device. The average current consumption of the device can be decreased by increasing the amount of time the device spends in standby period as compared to active conversion. Under the factory EEPROM settings, the device is configured to report an average of eight conversions with a conversion cycle time of 1 second by default.

Averaging can be used in both the continuous conversion mode and the one-shot mode.

GUID-4458ACD0-3959-4948-A98D-C22376BFAB5C-low.gifFigure 7-2 Averaging Timing Diagram