SNAS817C June   2021  – March 2023 HDC3020-Q1 , HDC3021-Q1 , HDC3022-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 I2C Interface Timing
    7. 7.7 Timing Diagram
    8. 7.8 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Factory Installed Polyimide Tape
      2. 8.3.2  Factory Installed IP67 Protection Cover
      3. 8.3.3  Wettable Flanks
      4. 8.3.4  Measurement of Relative Humidity and Temperature
      5. 8.3.5  Offset Error Correction: Accuracy Restoration
      6. 8.3.6  NIST Traceability of Relative Humidity and Temperature Sensor
      7. 8.3.7  Measurement Modes: Trigger-On Demand vs Auto Measurement
      8. 8.3.8  Heater
      9. 8.3.9  ALERT Output With Programmable Interrupts
      10. 8.3.10 Checksum Calculation
      11. 8.3.11 Programmable Offset of Relative Humidity and Temperature Results
    4. 8.4 Device Functional Modes
      1. 8.4.1 Sleep Mode vs Measurement Mode
    5. 8.5 Programming
      1. 8.5.1 I2C Interface
      2. 8.5.2 I2C Serial Bus Address Configuration
      3. 8.5.3 I2C Write - Send Device Command
      4. 8.5.4 I2C Read - Retrieve Single Data Result
      5. 8.5.5 I2C Read - Retrieve Multi Data Result
      6. 8.5.6 I2C Repeated START - Send Command and Retrieve Data Results
      7. 8.5.7 Command Table and Detailed Description
        1. 8.5.7.1 Reset
          1. 8.5.7.1.1 Soft Reset
          2. 8.5.7.1.2 I2C General Call Reset
        2. 8.5.7.2 Trigger-On Demand
        3. 8.5.7.3 Auto Measurement Mode
          1. 8.5.7.3.1 Auto Measurement Mode: Enable and Configure Measurement Interval
          2. 8.5.7.3.2 Auto Measurement Mode: Measurement Readout
          3. 8.5.7.3.3 Auto Measurement Mode: Exit
          4. 8.5.7.3.4 Auto Measurement Mode: Measurement History Readout
          5. 8.5.7.3.5 Override Default Device Power-On and Device-Reset State
        4. 8.5.7.4 ALERT Output Configuration
          1. 8.5.7.4.1 ALERT Output: Environmental Tracking of Temperature and Relative Humidity
          2. 8.5.7.4.2 ALERT Output: Representation of Environmental Thresholds and Default Threshold Values
          3. 8.5.7.4.3 ALERT Output: Steps to Calculate and Program Environmental Thresholds
          4. 8.5.7.4.4 ALERT Output: Deactivation of Environmental Tracking
          5. 8.5.7.4.5 ALERT Output: Transfer Thresholds into Non-Volatile Memory
        5. 8.5.7.5 Programmable Measurement Offset
          1. 8.5.7.5.1 Representation of Offset Value and Factory Shipped Default Value
          2. 8.5.7.5.2 Factory Shipped Default Offset Values
          3. 8.5.7.5.3 Calculate Relative Humidity Offset Value
          4. 8.5.7.5.4 Calculate Temperature Offset Value
          5. 8.5.7.5.5 Write an Offset Value
          6. 8.5.7.5.6 Verify a Programmed Offset Value
        6. 8.5.7.6 Status Register
        7. 8.5.7.7 Heater: Enable and Disable
        8. 8.5.7.8 Heater: Configure Level of Heater Current
        9. 8.5.7.9 Read NIST ID/Serial Number
  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
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
      3. 9.4.3 Storage and PCB Assembly
        1. 9.4.3.1 Storage and Handling
        2. 9.4.3.2 Soldering Reflow
        3. 9.4.3.3 Rework
        4. 9.4.3.4 Exposure to High Temperature and High Humidity Conditions
        5. 9.4.3.5 Bake/Rehydration Procedure
  10. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DEF|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3.8 Heater

The HDC302x-Q1 includes an integrated heating element that can be switched on to prevent or remove any condensation that may develop when the ambient environment approaches its dew point temperature. Additionally, the heater can be used to verify functionally of the integrated temperature sensor.

If the dew point of an application is continuously calculated and tracked, and the application firmware is written such that the device can detect a potential condensing situation (or a period of it), a software subroutine can be run, as a precautionary measure, to activate the onboard heater as an attempt to remove the condensate. The device shall continue to measure and track the %RH level after the heater is activated. Once the %RH reading goes to zero % (or near it), the heater can be subsequently turned off to allow the device to cool down. Cooling of the device can take several minutes, but the temperature measurement will continue to run to ensure the device goes back to normal operating condition before restarting the device for normal service.

Note that when the heater activates, the operating temperature of the device shall be limited based on the Recommended Operating Conditions THEATER limits.

It is important to recognize that, if using an open cavity sensor, the integrated heater evaporates condensate that forms on top of the humidity sensor. The heater does not remove any dissolved contaminants, however. If any contaminant residue is present, this may impact the accuracy of the humidity sensor. Refer to HDC3x Silicon User's Guide for more details on condensation removal.