SBASA74A January   2023  – April 2024 ADS9218 , ADS9219

ADVMIX  

  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  Thermal Information
    4. 5.4  Recommended Operating Conditions
    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: All Devices
    10. 5.10 Typical Characteristics: ADS9219
    11. 5.11 Typical Characteristics
    12. 5.12 Typical Characteristics: ADS9217
  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
      2. 6.3.2 Analog Input Bandwidth
      3. 6.3.3 ADC Transfer Function
      4. 6.3.4 Reference Voltage
      5. 6.3.5 Temperature Sensor
      6. 6.3.6 Data Averaging
      7. 6.3.7 Digital Down Converter
      8. 6.3.8 Data Interface
        1. 6.3.8.1 Data Frame Width
        2. 6.3.8.2 Synchronizing Multiple ADCs
        3. 6.3.8.3 Test Patterns for Data Interface
          1. 6.3.8.3.1 Fixed Pattern
          2. 6.3.8.3.2 Alternating Test Pattern
          3. 6.3.8.3.3 Digital Ramp
      9. 6.3.9 ADC Sampling Clock Input
    4. 6.4 Device Functional Modes
      1. 6.4.1 Reset
      2. 6.4.2 Power-Down Options
      3. 6.4.3 Normal Operation
      4. 6.4.4 Initialization Sequence
    5. 6.5 Programming
      1. 6.5.1 Register Write
      2. 6.5.2 Register Read
      3. 6.5.3 Multiple Devices: 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 Applications
      1. 8.2.1 Data Acquisition (DAQ) Circuit for ≤20kHz Input Signal Bandwidth
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Data Acquisition (DAQ) Circuit for ≤100kHz Input Signal Bandwidth
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Application Curves
      3. 8.2.3 Data Acquisition (DAQ) Circuit for ≤1MHz Input Signal Bandwidth
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Application Curves
    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 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 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

6.4.4 Initialization Sequence

As shown in Table 6-9, initialize the ADS921x with a sequence of register writes after device power-up or reset. Connect a free-running sampling clock to the ADC before executing the initialization sequence. The ADS921x registers are initialized with the default value after the initialization sequence is complete.

Table 6-9 ADS921x Initialization Sequence
STEP NUMBER REGISTER COMMENT
BANK ADDRESS VALUE[15:0]
1 0 0x03 0x0002 Select register bank 1
2 1 0xF6 0x0002 INIT_2 = 1
3 0 0x04 0x000B INIT_1 = 1011b
4 0 0x03 0x0010 Select register bank 2
5 2 0x12 0x0040 INIT_3 = 1
6 2 0x13 0x8000 INIT_4 = 1
7 2 0x0A 0x4000 INIT_5 = 1
8 Wait 10μs (min)
9 2 0x0A 0x0000 INIT_5 = 0
10 0 0x03 0x0002 Select register bank 1
11 1 0xF6 0x0000 INIT_2 = 0
12 0 0x03 0x0010 Select register bank 2
13 2 0x13 0x0000 INIT_5 = 0
14 2 0x12 0x0000 INIT_4 = 0
15 0 0x04 0x0000 INIT_1 = 0
16 0 0x03 0x0002 Select register bank 1
17 1 0x33 0x0030 Write INIT_KEY
18 1 0xF4 0x0000 INIT = 0
19 1 0xF4 0x0002 INIT = 1
20 Wait 1ms (min)
21 1 0xF4 0x0000 INIT = 0
22 Wait 1ms (min)
23 1 0x33 0x0000 INIT_KEY = 0
24 1 0x0D User defined Enable gain error calibration and select ADC output data format
25 1 0x33 0x2040 Enable gain error calibration