SBAS350G June   2005  – January 2021 ADS1232 , ADS1234

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Noise Performance
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Analog Inputs (AINPX, AINNX)
      2. 8.3.2  Temperature Sensor (ADS1232 Only)
      3. 8.3.3  Low-Noise PGA
        1. 8.3.3.1 PGA Bypass Capacitor
      4. 8.3.4  Voltage Reference Inputs (REFP, REFN)
      5. 8.3.5  Clock Sources
      6. 8.3.6  Digital Filter Frequency Response
      7. 8.3.7  Settling Time
      8. 8.3.8  Data Rate
      9. 8.3.9  Data Format
      10. 8.3.10 Data Ready and Data Output (DRDY/DOUT)
      11. 8.3.11 Serial Clock Input (SCLK)
      12. 8.3.12 Data Retrieval
    4. 8.4 Device Functional Modes
      1. 8.4.1 Offset Calibration Mode
      2. 8.4.2 Standby Mode
      3. 8.4.3 Standby Mode With Offset-Calibration
      4. 8.4.4 Power-Down Mode
      5. 8.4.5 Power-Up Sequence
      6. 8.4.6 Summary of Serial Interface Waveforms
  9. 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
  10. 10Power Supply Recommendations
    1. 10.1 Power-Supply Decoupling
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

8.4.5 Power-Up Sequence

When powering up the ADS123x, follow the prescribed PWDN pin sequence as shown in Figure 8-15. At power-up, hold the PWDN pin low until after AVDD and DVDD have stabilized above the minimum specified voltage levels. After an initial delay where PWDN must be held low (t15), take PWDN high then toggle PWDN low to high with pulse durations (t16 and t17) as shown in Figure 8-15 and Table 8-13. The ADC then begins operation as shown in Figure 8-14 and Table 8-12. Control PDWN by the host processor to provide the required power-on timing.

 

GUID-D57D7234-F7A7-412E-A440-7BBC274FAE2A-low.gif Figure 8-15 Power-Up Timing Sequence
Table 8-13 Power-up Timing Requirements for Figure 8-15
PARAMETER MIN(1) UNIT
t15 Delay time, PWDN high after AVDD, DVDD stable 10 µs
t16 Pulse duration, PWDN high 26 µs
t17 Pulse duration, PWDN low 26 µs
(1) fCLK = 4.9152 MHz. For fCLK < 4.9152 MHz, adjust the PWDN delay time and pulse duration accordingly.