SBASAG2C December   2023  – March 2025 ADS9227 , ADS9228 , ADS9229

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Thermal Information
    4. 6.4  Recommended Operating Conditions
    5. 6.5  Electrical Characteristics
    6. 6.6  Timing Requirements
    7. 6.7  Switching Characteristics
    8. 6.8  Timing Diagrams
    9. 6.9  Typical Characteristics: All Devices
    10. 6.10 Typical Characteristics: ADS9229
    11. 6.11 Typical Characteristics: ADS9228
    12. 6.12 Typical Characteristics: ADS9227
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Analog Inputs
      2. 7.3.2  Analog Input Bandwidth
      3. 7.3.3  ADC Transfer Function
      4. 7.3.4  Reference
        1. 7.3.4.1 Internal Reference Voltage
        2. 7.3.4.2 External Reference Voltage
      5. 7.3.5  Temperature Sensor
      6. 7.3.6  Data Averaging
      7. 7.3.7  Digital Down Converter
      8. 7.3.8  Data Interface
        1. 7.3.8.1 Data Frame Width
        2. 7.3.8.2 ADC Output Data Randomizer
        3. 7.3.8.3 Synchronizing Multiple ADCs
      9. 7.3.9  Test Patterns for Data Interface
        1. 7.3.9.1 Fixed Pattern
        2. 7.3.9.2 Digital Ramp
        3. 7.3.9.3 Alternating Test Pattern
      10. 7.3.10 ADC Sampling Clock Input
    4. 7.4 Device Functional Modes
      1. 7.4.1 Reset
      2. 7.4.2 Power-Down Options
      3. 7.4.3 Normal Operation
      4. 7.4.4 Initialization Sequence
    5. 7.5 Programming
      1. 7.5.1 Register Write
      2. 7.5.2 Register Read
      3. 7.5.3 Multiple Devices: Daisy-Chain Topology for SPI Configuration
        1. 7.5.3.1 Register Write With Daisy-Chain
        2. 7.5.3.2 Register Read With Daisy-Chain
  9. 8 Register Map
    1. 8.1 Register Bank 0
    2. 8.2 Register Bank 1
    3. 8.3 Register Bank 2
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Data Acquisition (DAQ) Circuit for ≤20kHz Input Signal Bandwidth
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Data Acquisition (DAQ) Circuit for ≤100kHz Input Signal Bandwidth
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Application Curves
      3. 9.2.3 Data Acquisition (DAQ) Circuit for ≤1MHz Input Signal Bandwidth
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 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
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

7.3.5 Temperature Sensor

The ADS922x features a 10-bit temperature sensor for measuring temperature inside the device. Follow the sequence listed in Table 7-2 to read the temperature sensor output with the SPI. Read the temperature sensor data at anytime independent of the ADC data interface.

The transfer function for the temperature sensor is given by Equation 1:

Equation 1. Temperature   =   -85.0172   +   (10 bit output   × 0.24918 )   °C
Table 7-2 Sequence to Read Temperature Sensor Output
REGISTER ADDRESS REGISTER BANK VALUE COMMENT
0x90 1 0x4000 Write register to load temperature sensor output in address 0x91
0x91 1 10 bit temperature sensor data Read register for temperature sensor output
0x90 1 0x0000 Write register