SNAS649B October   2014  – December 2015 HDC1008

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Typical Application
  5. 5 Revision History
  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 Electrical Characteristics
    7. 7.7 I2C Interface Timing Requirements
    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 Power Consumption
      2. 8.3.2 Voltage Supply Monitoring
      3. 8.3.3 Heater
    4. 8.4 Device Functional Modes
    5. 8.5 Programming
      1. 8.5.1 I2C Serial Bus Address Configuration
      2. 8.5.2 I2C Interface
        1. 8.5.2.1 Serial Bus Address
        2. 8.5.2.2 Read and Write Operations
        3. 8.5.2.3 Device Measurement Configuration
    6. 8.6 Register Map
      1. 8.6.1 Temperature Register
      2. 8.6.2 Humidity Register
      3. 8.6.3 Configuration Register
      4. 8.6.4 Serial Number Registers
  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 Do's and Don'ts
      1. 9.3.1 Soldering
      2. 9.3.2 Hydration Procedure
      3. 9.3.3 Chemical Exposure
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Surface Mount
      2. 11.1.2 Stencil Printing Process
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    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 Layout

11.1 Layout Guidelines

The Relative Humidity sensor element is located on the bottom side of the package. It is positioned between the two rows of bumps.

It is recommended to not route any traces below the sensor element. Moreover, the external components, such as pull-up resistors and bypass capacitors need to be placed next to the 2 rows of bumps or on the bottom side of the PCB in order to guarantee a good air flow.

11.1.1 Surface Mount

Two types of PCB land patterns are used for surface mount packages:

  1. Non-solder mask defined (NSMD)
  2. Solder mask defined (SMD)

Pros and cons of NSMD and SMD:

  1. The NSMD configuration is preferred due to its tighter control of the copper etch process and a reduction in the stress concentration points on the PCB side compared to SMD configuration.
  2. A copper layer thickness of less than 1 oz. is recommended to achieve higher solder joint stand-off. A 1 oz. (35 micron) or greater copper thickness causes a lower effective solder joint stand-off, which may compromise solder joint reliability.
  3. For the NSMD pad geometry, the trace width at the connection to the land pad should not exceed 2/3 of the pad diameter.

HDC1008 pkg02_solder_mask_detail_snas643.gif Figure 17. Solder Mask

11.1.2 Stencil Printing Process

  1. Use laser cutting followed by electro-polishing for stencil fabrication.
  2. If possible, offset apertures from land pads to maximize separation and minimize possibility of bridging for DSBGA packages.
  3. Use Type 3 (25 to 45 micron particle size range) or finer solder paste for printing.

HDC1008 pkg03_solder_paste_ex_snas643.gif Figure 18. Solder Paste

11.2 Layout Example

The only component next to the device is the supply bypass capacitor. Since the relative humidity is dependent on the temperature, the HDC1008 should be positioned away from hot points present on the board such as battery, display or micro-controller. Slots around the device can be used to reduce the thermal mass for a quicker response to environmental changes.

HDC1008 LAYERS.gif Figure 19. HDC1008 Layout