SLAS904F October   2012  – May 2016 ADS42LB49 , ADS42LB69

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: ADS42LB69 (16-Bit)
    6. 6.6  Electrical Characteristics: ADS42LB49 (14-Bit)
    7. 6.7  Electrical Characteristics: General
    8. 6.8  Digital Characteristics
    9. 6.9  Timing Requirements: General
    10. 6.10 Timing Requirements: DDR LVDS Mode
    11. 6.11 Timing Requirements: QDR LVDS Mode
    12. 6.12 Typical Characteristics: ADS42LB69
    13. 6.13 Typical Characteristics: ADS42LB49
    14. 6.14 Typical Characteristics: Common
    15. 6.15 Typical Characteristics: Contour
      1. 6.15.1 Spurious-Free Dynamic Range (SFDR): General
      2. 6.15.2 Signal-to-Noise Ratio (SNR): ADS42LB69
      3. 6.15.3 Signal-to-Noise Ratio (SNR): ADS42LB49
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Digital Gain
      2. 8.3.2 Input Clock Divider
      3. 8.3.3 Overrange Indication
        1. 8.3.3.1 OVR in a QDR Pinout
        2. 8.3.3.2 OVR in a DDR Pinout
        3. 8.3.3.3 Programming Threshold for Fast OVR
      4. 8.3.4 LVDS Buffer
      5. 8.3.5 Output Data Format
    4. 8.4 Device Functional Modes
      1. 8.4.1 Digital Output Information
        1. 8.4.1.1 Output Interface
        2. 8.4.1.2 DDR LVDS Outputs
        3. 8.4.1.3 QDR LVDS Outputs
    5. 8.5 Programming
      1. 8.5.1 Device Configuration
      2. 8.5.2 Details of Serial Interface
        1. 8.5.2.1 Register Initialization
        2. 8.5.2.2 Serial Register Write
        3. 8.5.2.3 Serial Register Readout
    6. 8.6 Register Maps
      1. 8.6.1 Description of Serial Interface Registers
        1. 8.6.1.1  Register 6 (offset = 06h) [reset = 80h]
        2. 8.6.1.2  Register 7 (offset = 07h) [reset = 00h]
        3. 8.6.1.3  Register 8 (offset = 08h) [reset = 00h]
        4. 8.6.1.4  Register B (offset = 0Bh) [reset = 00h]
        5. 8.6.1.5  Register C (offset = 0Ch) [reset = 00h]
        6. 8.6.1.6  Register D (offset = 0Dh) [reset = 6Ch]
        7. 8.6.1.7  Register F (offset = 0Fh) [reset = 00h]
        8. 8.6.1.8  Register 10 (offset = 10h) [reset = 00h]
        9. 8.6.1.9  Register 11 (offset = 11h) [reset = 00h]
        10. 8.6.1.10 Register 12 (offset = 12h) [reset = 00h]
        11. 8.6.1.11 Register 13 (offset = 13h) [reset = 00h]
        12. 8.6.1.12 Register 14 (offset = 14h) [reset = 00h]
        13. 8.6.1.13 Register 15 (offset = 15h) [reset = 00h]
        14. 8.6.1.14 Register 16 (offset = 16h) [reset = 00h]
        15. 8.6.1.15 Register 17 (offset = 17h) [reset = 00h]
        16. 8.6.1.16 Register 18 (offset = 18h) [reset = 00h]
        17. 8.6.1.17 Register 1F (offset = 1Fh) [reset = 7Fh]
        18. 8.6.1.18 Register 20 (offset = 20h) [reset = 00h]
  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
        1. 9.2.2.1 Analog Input
          1. 9.2.2.1.1 Drive Circuit Requirements
          2. 9.2.2.1.2 Driving Circuit
          3. 9.2.2.1.3 Using the ADS42LBx9 In Time-Domain, Low-Frequency Pulse Applications
        2. 9.2.2.2 Clock Input
        3. 9.2.2.3 SNR and Clock Jitter
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Related Links
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

11 Layout

11.1 Layout Guidelines

  • The length of the positive and negative traces of a differential pair must be matched to within 2 mils of each other.
  • Each differential pair length must be matched within 10 mils of each other.
  • When the ADC is used on the same printed circuit board (PCB) with a digital intensive component [such as a field-programmable gate array (FPGA) or application-specific integrated circuit (ASIC)], use separate digital and analog ground planes to minimize undesired coupling. Note that these ground planes must not overlap.
  • Connect decoupling capacitors directly to ground and place these capacitors close to the ADC power pins and the power-supply pins to filter high-frequency current transients directly to the ground plane, as illustrated in Figure 126.
  • Ground and power planes must be wide enough to keep the impedance very low. In a multilayer PCB, dedicate one layer to ground and another to power planes.
ADS42LB49 ADS42LB69 ai_capacitor_placement_slas904.gif Figure 126. Recommended Placement of Power-Supply Decoupling Capacitors

11.2 Layout Example

ADS42LB49 ADS42LB69 ai_layout_slas904.gif Figure 127. Example Layout
ADS42LB49 ADS42LB69 ai_ex_pcb_stack_slas904.gif Figure 128. Example PCB Layer Stack