JAJSFY8A August   2018  – November 2018 ADS1119

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      電圧、電流、および温度監視アプリケーション
  4. 4 改訂履歴
  5. 5 概要（続き）
  6. 6 Pin Configuration and Functions
    1.     Pin 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 Timing Requirements
    7. 7.7 I2C Switching Characteristics
    8. 7.8 Typical Characteristics
  8. 8 Parameter Measurement Information
    1. 8.1 Noise Performance
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Multiplexer
      2. 9.3.2 Rail-to-Rail Input Buffers and Programmable Gain Stage
      3. 9.3.3 Voltage Reference
      4. 9.3.4 Modulator and Internal Oscillator
      5. 9.3.5 Digital Filter
      6. 9.3.6 Conversion Times
      7. 9.3.7 Offset Calibration
    4. 9.4 Device Functional Modes
      1. 9.4.1 Power-Up and Reset
        1. 9.4.1.1 Power-On Reset
        2. 9.4.1.2 RESET Pin
        3. 9.4.1.3 Reset by Command
      2. 9.4.2 Conversion Modes
        1. 9.4.2.1 Single-Shot Conversion Mode
        2. 9.4.2.2 Continuous Conversion Mode
      3. 9.4.3 Power-Down Mode
    5. 9.5 Programming
      1. 9.5.1 I2C Interface
        1. 9.5.1.1 I2C Address
        2. 9.5.1.2 Serial Clock (SCL) and Serial Data (SDA)
        3. 9.5.1.3 Data Ready (DRDY)
        4. 9.5.1.4 Interface Speed
        5. 9.5.1.5 Data Transfer Protocol
        6. 9.5.1.6 I2C General Call (Software Reset)
        7. 9.5.1.7 Timeout
      2. 9.5.2 Data Format
      3. 9.5.3 Commands
        1. 9.5.3.1 Command Latching
        2. 9.5.3.2 RESET (0000 011x)
        3. 9.5.3.3 START/SYNC (0000 100x)
        4. 9.5.3.4 POWERDOWN (0000 001x)
        5. 9.5.3.5 RDATA (0001 xxxx)
        6. 9.5.3.6 RREG (0010 0rxx)
        7. 9.5.3.7 WREG (0100 00xx dddd dddd)
      4. 9.5.4 Reading Data and Monitoring for New Conversion Results
    6. 9.6 Register Map
      1. 9.6.1 Configuration and Status Registers
      2. 9.6.2 Register Descriptions
        1. 9.6.2.1 Configuration Register (address = 0h) [reset = 00h]
          1. Table 10. Configuration Register Field Descriptions
        2. 9.6.2.2 Status Register (address = 1h) [reset = 00h]
          1. Table 11. Status Register Field Descriptions
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Interface Connections
      2. 10.1.2 Connecting Multiple Devices on the Same I2C Bus
      3. 10.1.3 Unused Inputs and Outputs
      4. 10.1.4 Analog Input Filtering
      5. 10.1.5 External Reference and Ratiometric Measurements
      6. 10.1.6 Establishing Proper Limits on the Absolute Input Voltage
      7. 10.1.7 Pseudo Code Example
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Voltage Monitoring
        2. 10.2.2.2 High-Side Current Measurement
        3. 10.2.2.3 Thermistor Measurement
        4. 10.2.2.4 Register Settings
      3. 10.2.3 Application Curve
  11. 11Power Supply Recommendations
    1. 11.1 Power-Supply Sequencing
    2. 11.2 Power-Supply Decoupling
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13デバイスおよびドキュメントのサポート
    1. 13.1 デバイス・サポート
      1. 13.1.1 デベロッパー・ネットワークの製品に関する免責事項
    2. 13.2 ドキュメントのサポート
      1. 13.2.1 関連資料
    3. 13.3 ドキュメントの更新通知を受け取る方法
    4. 13.4 コミュニティ・リソース
    5. 13.5 商標
    6. 13.6 静電気放電に関する注意事項
    7. 13.7 Glossary
  14. 14メカニカル、パッケージ、および注文情報

10.2.2 Detailed Design Procedure

In order to take one reading from each of the three input signals within 100 ms, the ADS1119 must use a data rate of 90 SPS or faster. When using a data rate setting of 90 SPS, every conversion takes approximately 11.3 ms according to Table 4. Consequently, all three signals can be measured within approximately 34 ms when also accounting for the time to read conversion results and to write new configuration register settings between conversions.

All three signal measurements use a single-ended measurement implementation. The voltage and current measurements use the GND connection within the MUX, whereas the thermistor measurement uses an external GND connection through AIN1 to showcase the two different options for implementing a single-ended measurement.

RC filters are provided on all three analog inputs of the device, which act as antialiasing filters and to limit the current into the analog inputs in case of overvoltage events. The filter component values are chosen according to the guidelines in the Analog Input Filtering section as RF = 1 kΩ and CF = 100 nF to create a filter corner frequency of fC = 1 / (2π · RF · CF) = 1.6 kHz.