JAJSQP4 February   2024 ADS1288

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  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: 1.65V ≤ IOVDD ≤ 1.95V and 2.7V ≤ IOVDD ≤ 3.6V
    7. 5.7 Switching Characteristics: 1.65V ≤ IOVDD ≤ 1.95V and 2.7V ≤ IOVDD ≤ 3.6V
    8. 5.8 Timing Diagrams
    9. 5.9 Typical Characteristics
  7. 6 Parameter Measurement Information
    1. 6.1 Noise Performance
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Analog Input
      2. 7.3.2 PGA and Buffer
        1. 7.3.2.1 Programmable Gain Amplifier (PGA)
        2. 7.3.2.2 Buffer Operation (PGA Bypass)
      3. 7.3.3 Voltage Reference Input
      4. 7.3.4 IOVDD Power Supply
      5. 7.3.5 Modulator
        1. 7.3.5.1 Modulator Overdrive
      6. 7.3.6 Digital Filter
        1. 7.3.6.1 Sinc Filter Section
        2. 7.3.6.2 FIR Filter Section
        3. 7.3.6.3 Group Delay and Step Response
          1. 7.3.6.3.1 Linear Phase Response
          2. 7.3.6.3.2 Minimum Phase Response
        4. 7.3.6.4 HPF Stage
      7. 7.3.7 Clock Input
      8. 7.3.8 GPIO
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power-Down Mode
      2. 7.4.2 Reset
      3. 7.4.3 Synchronization
        1. 7.4.3.1 Pulse-Sync Mode
        2. 7.4.3.2 Continuous-Sync Mode
      4. 7.4.4 Sample Rate Converter
      5. 7.4.5 Offset and Gain Calibration
        1. 7.4.5.1 OFFSET Register
        2. 7.4.5.2 GAIN Register
        3. 7.4.5.3 Calibration Procedure
    5. 7.5 Programming
      1. 7.5.1 Serial Interface
        1. 7.5.1.1 Chip Select (CS)
        2. 7.5.1.2 Serial Clock (SCLK)
        3. 7.5.1.3 Data Input (DIN)
        4. 7.5.1.4 Data Output (DOUT)
        5. 7.5.1.5 Data Ready (DRDY)
      2. 7.5.2 Conversion Data Format
      3. 7.5.3 Commands
        1. 7.5.3.1  Single Byte Command
        2. 7.5.3.2  WAKEUP: Wake Command
        3. 7.5.3.3  STANDBY: Software Power-Down Command
        4. 7.5.3.4  SYNC: Synchronize Command
        5. 7.5.3.5  RESET: Reset Command
        6. 7.5.3.6  Read Data Direct
        7. 7.5.3.7  RDATA: Read Conversion Data Command
        8. 7.5.3.8  RREG: Read Register Command
        9. 7.5.3.9  WREG: Write Register Command
        10. 7.5.3.10 OFSCAL: Offset Calibration Command
        11. 7.5.3.11 GANCAL: Gain Calibration Command
  9. 8 Register Map
    1. 8.1 Register Descriptions
      1. 8.1.1 ID/SYNC: Device ID, SYNC Register (Address = 00h) [Reset = xxxx0010b]
      2. 8.1.2 CONFIG0: Configuration Register 0 (Address = 01h) [Reset = 92h]
      3. 8.1.3 CONFIG1: Configuration Register 1 (Address = 02h) [Reset = 10h]
      4. 8.1.4 HPF0, HPF1: High-Pass Filter Registers (Address = 03h, 04h) [Reset = 32h, 03h]
      5. 8.1.5 OFFSET0, OFFSET1, OFFSET2: Offset Calibration Registers (Address = 05h, 06h, 07h) [Reset = 00h, 00h, 00h]
      6. 8.1.6 GAIN0, GAIN1, GAIN2: Gain Calibration Registers (Address = 08h, 09h, 0Ah) [Reset = 00h, 00h, 40h]
      7. 8.1.7 GPIO: Digital Input/Output Register (Address = 0Bh) [Reset = 000xx000b]
      8. 8.1.8 SRC0, SRC1: Sample Rate Converter Registers (Address = 0Ch, 0Dh) [Reset = 00h, 80h]
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
      1. 9.3.1 Analog Power Supplies
      2. 9.3.2 Digital Power Supply
      3. 9.3.3 Grounds
      4. 9.3.4 Thermal Pad
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 ドキュメントの更新通知を受け取る方法
    2. 10.2 サポート・リソース
    3. 10.3 Trademarks
    4. 10.4 静電気放電に関する注意事項
    5. 10.5 用語集
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

9.2.3 Application Curves

Table 9-1 lists the effect of geophone source resistance (RS) and the effect of input current noise to total noise performance. Geophone RS = 1000Ω, 5000Ω, and two values of input current noise taken from the input current noise distribution of Figure 9-2. Input current noise values = 1.5pA/√Hz and 3pA/√Hz are evaluated. Geophone RS thermal noise, current noise × RS, and ADC input-referred noise are summed to derive total noise.

GUID-20221114-SS0I-DXHW-SX0N-DG35LMHDJXLW-low.svg Figure 9-2 PGA Input Current Noise Distribution
Table 9-1 Total Noise
RS (Ω) GAIN RS NOISE (μV) in NOISE (pA/√Hz) in × RS NOISE (μV) ADC NOISE  (μV) TOTAL NOISE (μV)
1000 1 0.06 1.5 0.024 1.4 1.4
0.06 3 0.048 1.4
16 0.06 1.5 0.024 0.28 0.29
0.06 3 0.048 0.29
5000 1 0.13 1.5 0.11 1.4 1.41
0.13 3 0.22 1.41
16 0.13 1.5 0.11 0.28 0.33
0.13 3 0.22 0.38

The analysis data is over a 206Hz noise bandwidth (fDATA = 500SPS). The data shows the greatest of the total noise increase compared to ADC noise alone is with 5000Ω geophone source resistance, PGA gain = 16, and in = 3pA/√Hz. The 1000Ω geophone source resistance shows an insignificant noise increase under the same condition.