SBASAX3A May   2025  – September 2025 ADS9326 , ADS9327

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  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  Electrical Characteristics: AVDD = 5V
    7. 6.7  Electrical Characteristics: AVDD = 3.3V
    8. 6.8  Timing Requirements
    9. 6.9  Switching Characteristics
    10. 6.10 Timing Diagrams
    11. 6.11 Typical Characteristics
  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 Reference
        1. 7.3.2.1 Internal Reference
          1. 7.3.2.1.1 Selectable Internal Reference with 5V AVDD
        2. 7.3.2.2 External Reference
        3. 7.3.2.3 External Reference With External Reference Buffer
      3. 7.3.3 ADC Transfer Function
      4. 7.3.4 Data Interface
      5. 7.3.5 Programmable Data Averaging Filter
        1. 7.3.5.1 Simple Average
          1. 7.3.5.1.1 Simple Average with Noncontinuous CONVST
        2. 7.3.5.2 Moving Average
      6. 7.3.6 CRC on Output Data Interface
      7. 7.3.7 ADC Output Data Randomizer
      8. 7.3.8 Data Frame Width
      9. 7.3.9 Daisy-Chain Mode
        1. 7.3.9.1 Daisy-Clock Mode
    4. 7.4 Device Functional Modes
      1. 7.4.1 Reset
      2. 7.4.2 Normal Operation
      3. 7.4.3 Low-Latency Mode
      4. 7.4.4 CS-CONVST Short Mode
      5. 7.4.5 Register Read Mode
      6. 7.4.6 Initialization Sequence
    5. 7.5 Programming
      1. 7.5.1 SPI Frame Length for Register Operations
      2. 7.5.2 Register Map Lock
      3. 7.5.3 Register Write
      4. 7.5.4 Register Read
  9. 8 Register Map: ADS9327
    1. 8.1 Register Bank 0
    2. 8.2 Register Bank 1
    3. 8.3 Register Bank 2
  10. 9 Register Map: ADS9326
    1. 9.1 Register Bank 0
    2. 9.2 Register Bank 1
    3. 9.3 Register Bank 2
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Analog 1VPP Sine-Cosine Encoder Interface
      2. 10.2.2 Design Requirements
      3. 10.2.3 Detailed Design Procedure
    3. 10.3 Power Supply Recommendations
    4. 10.4 Layout
      1. 10.4.1 Layout Guidelines
      2. 10.4.2 Layout Example
  12. 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
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Mechanical Data

7.3.2 Reference

The ADS932x has a precision, low-drift voltage reference internal to the device. For best performance, filter the internal reference noise by connecting a 1µF ceramic bypass capacitor to the REFIO pin. On power-up, as described in Table 7-1, the reference source is selected by writing to PD_REF in address 0x0C in register bank 1.

Table 7-1 Reference Source Selection
PD_REF REGISTER VALUE ADC REFERENCE SOURCE
10b Internal reference is active.
11b Internal reference is inactive. Force an external reference with REFIO (pin 9).