SBASAQ6 April   2024 ADS9813

ADVANCE INFORMATION  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Timing Requirements
    7. 5.7 Switching Characteristics
    8. 5.8 Timing Diagrams
    9. 5.9 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Analog Inputs
        1. 6.3.1.1 Input Clamp Protection Circuit
        2. 6.3.1.2 Programmable Gain Amplifier (PGA)
        3. 6.3.1.3 Wide-Common-Mode Voltage Rejection Circuit
      2. 6.3.2 ADC Transfer Function
      3. 6.3.3 ADC Sampling Clock Input
      4. 6.3.4 Synchronizing Multiple ADCs
      5. 6.3.5 Reference Voltage
      6. 6.3.6 Test Patterns for Data Interface
        1. 6.3.6.1 Fixed Pattern
        2. 6.3.6.2 Digital Ramp
        3. 6.3.6.3 Alternating Test Pattern
    4. 6.4 Device Functional Modes
      1. 6.4.1 Reset
      2. 6.4.2 Power-Down
      3. 6.4.3 Initialization Sequence
      4. 6.4.4 Normal Operation
    5. 6.5 Programming
      1. 6.5.1 Register Write
      2. 6.5.2 Register Read
      3. 6.5.3 Multiple Devices in a Daisy-Chain Topology for SPI Configuration
        1. 6.5.3.1 Register Write With Daisy-Chain
        2. 6.5.3.2 Register Read With Daisy-Chain
  8. 7 Register Map
    1. 7.1 Register Bank 0
    2. 7.2 Register Bank 1
    3. 7.3 Register Bank 2
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Parametric Measurement Unit (PMU)
      2. 8.2.2 Design Requirements
      3. 8.2.3 Detailed Design Procedure
      4. 8.2.4 Application Curve
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Mechanical Data

Package Options

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

6.5.3.2 Register Read With Daisy-Chain

Figure 6-14 depicts an SPI waveform for reading registers in daisy-chain. Steps for reading registers from N ADCs connected in daisy-chain are:

  1. A register read is enabled by writing to the following registers using the register write with daisy-chain operation:
    1. Write to PAGE_SEL to select the desired register bank
    2. Enable register reads by writing SPI_RD_EN = 0b (default on power-up)
  2. With the register bank selected and SPI_RD_EN = 0b, the controller reads register data in the following two steps:
    1. The N × 24-bit SPI frame containing the 8-bit register address is read: N-times {0xFE, 0x00, 8-bit register address}
    2. The N × 24-bit SPI frame to read out register data is read: N-times {0xFF, 0xFF, 0xFF}

The 0xFE in step 2a configures the ADC for register reads from the specified 8-bit address. At the end of step 2a, the output shift register in the ADC is loaded with register data. The ADC returns the 8-bit register address and corresponding 16-bit register data in step 2b.

GUID-C8066DD4-9915-4A30-96B0-31A295895D47-low.svg Figure 6-14 Register Read With Daisy-Chain