SLASE60B September   2015  – January 2019 ADC31JB68

PRODUCTION DATA.  

  1. 1 Features
    1.     Transmitted Eye at Output of 18-Inch, 5-mil. FR4 Microstrip Trace at 5 Gb/s With Optimized De-Emphasis
  2. 2 Applications
  3. 3 Description
    1.     Spectrum With –1-dBFS, 450-MHz Input
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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: Converter Performance
    6. 6.6 Electrical Characteristics: Power Supply
    7. 6.7 Electrical Characteristics: Interface
    8. 6.8 Timing Requirements
    9. 6.9 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Interface Circuits
  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 and Input Buffer
      2. 8.3.2  Amplitude and Phase Imbalance Correction
      3. 8.3.3  Over-Range Detection
      4. 8.3.4  Input Clock Divider
      5. 8.3.5  SYSREF Detection Gate
      6. 8.3.6  Serial Differential Output Drivers
        1. 8.3.6.1 De-Emphasis Equalization
        2. 8.3.6.2 Serial Lane Inversion
      7. 8.3.7  ADC Core Calibration
      8. 8.3.8  Data Format
      9. 8.3.9  JESD204B Supported Features
      10. 8.3.10 JESD204B Interface
      11. 8.3.11 Transport Layer Configuration
        1. 8.3.11.1 Lane Configuration
        2. 8.3.11.2 Frame Format
        3. 8.3.11.3 ILA Information
      12. 8.3.12 Test Pattern Sequences
      13. 8.3.13 JESD204B Link Initialization
        1. 8.3.13.1 Frame Alignment
        2. 8.3.13.2 Code Group Synchronization
      14. 8.3.14 SPI
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power-Down and Sleep Modes
    5. 8.5 Register Map
      1. 8.5.1 Register Descriptions
        1. 8.5.1.1  CONFIG_A (address = 0x0000) [reset = 0x3C]
          1. Table 6. CONFIG_A
        2. 8.5.1.2  DEVICE CONFIG (address = 0x0002) [reset = 0x00]
          1. Table 7. DEVICE CONFIG
        3. 8.5.1.3  CHIP_TYPE (address = 0x0003 ) [reset = 0x03]
          1. Table 8. CHIP_TYPE
        4. 8.5.1.4  CHIP_ID (address = 0x0005, 0x0004) [reset = 0x00, 0x1B]
          1. Table 9. CHIP_ID
        5. 8.5.1.5  CHIP_VERSION (address =0x0006) [reset = 0x00]
          1. Table 10. CHIP_VERSION
        6. 8.5.1.6  VENDOR_ID (address = 0x000D, 0x000C) [reset = 0x04, 0x51]
          1. Table 11. VENDOR_ID
        7. 8.5.1.7  SPI_CFG (address = 0x0010 ) [reset = 0x01]
          1. Table 12. SPI_CFG
        8. 8.5.1.8  OM1 (Operational Mode 1) (address = 0x0012) [reset = 0xC1]
          1. Table 13. OM1 (Operational Mode 1)
        9. 8.5.1.9  OM2 (Operational Mode 2) (address = 0x0013) [reset = 0x20]
          1. Table 14. OM2 (Operational Mode 2)
        10. 8.5.1.10 IMB_ADJ (Imbalance Adjust) (address = 0x0014) [reset = 0x00]
          1. Table 15. IMB_ADJ (Imbalance Adjust)
        11. 8.5.1.11 OVR_EN (Over-Range Enable) (address = 0x003A) [reset = 0x00]
          1. Table 16. OVR_EN (Over-Range Enable)
        12. 8.5.1.12 OVR_HOLD (Over-Range Hold) (address = 0x003B) [reset = 0x00]
          1. Table 17. OVR_HOLD (Over-Range Hold)
        13. 8.5.1.13 OVR_TH (Over-Range Threshold) (address = 0x003C) [reset = 0x00]
          1. Table 18. OVR_TH (Over-Range Threshold)
        14. 8.5.1.14 DC_MODE (DC Offset Correction Mode) (address = 0x003D) [reset = 0x00]
          1. Table 19. DC_MODE (DC Offset Correction Mode)
        15. 8.5.1.15 SER_CFG (Serial Lane Transmitter Configuration) (address = 0x0047) [reset = 0x00]
          1. Table 20. SER_CFG (Serial Lane Transmitter Configuration)
        16. 8.5.1.16 JESD_CTRL1 (JESD Configuration Control 1) (address = 0x0060) [reset = 0x7F]
          1. Table 21. JESD_CTRL1 (JESD Configuration Control 1)
        17. 8.5.1.17 JESD_CTRL2 (JESD Configuration Control 2) (address = 0x0061) [reset = 0x00]
          1. Table 22. JESD_CTRL2 (JESD Configuration Control 2)
        18. 8.5.1.18 JESD_RSTEP (JESD Ramp Pattern Step) (address = 0x0063, 0x0062) [reset = 0x00, 0x01]
          1. Table 23. JESD_RSTEP (JESD Ramp Pattern Step)
        19. 8.5.1.19 SER_INV (Serial Lane Inversion Control) (address = 0x0064) [reset = 0x00]
          1. Table 24. SER_INV (Serial Lane Inversion Control)
        20. 8.5.1.20 JESD_STATUS (JESD Link Status) (address = 0x006C) [reset = N/A]
          1. Table 25. JESD_STATUS (JESD Link Status)
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Optimizing Converter Performance
        1. 9.1.1.1 Internal Noise Sources
        2. 9.1.1.2 External Noise Sources
      2. 9.1.2 Analog Input Considerations
        1. 9.1.2.1 Differential Analog Inputs and Full Scale Range
        2. 9.1.2.2 Analog Input Network Model
        3. 9.1.2.3 Input Bandwidth
        4. 9.1.2.4 Driving the Analog Input
        5. 9.1.2.5 Clipping and Over-Range
      3. 9.1.3 CLKIN, SYSREF, and SYNCb Input Considerations
        1. 9.1.3.1 Driving the CLKIN+ and CLKIN– Input
        2. 9.1.3.2 Driving the SYSREF Input
        3. 9.1.3.3 SYSREF Signaling
        4. 9.1.3.4 SYSREF Timing
        5. 9.1.3.5 Effectively Using the Detection Gate Feature
        6. 9.1.3.6 Driving the SYNCb Input
      4. 9.1.4 Output Serial Interface Considerations
        1. 9.1.4.1 Output Serial-Lane Interface
        2. 9.1.4.2 Voltage Swing and De-Emphasis Optimization
        3. 9.1.4.3 Minimizing EMI
      5. 9.1.5 JESD204B System Considerations
        1. 9.1.5.1 Frame and LMFC Clock Alignment Procedure
        2. 9.1.5.2 Link Interruption
        3. 9.1.5.3 Clock Configuration Examples
      6. 9.1.6 SPI
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Design Procedure
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
    1. 10.1 Power Supply Design
    2. 10.2 Decoupling
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.1.4.2 Voltage Swing and De-Emphasis Optimization

Voltage swing control (VOD) compensates for attenuation across all frequencies through the channel at the expense of power consumption. Increasing the voltage swing increases the power consumption. De-emphasis (DEM) compensates for the frequency dependent attenuation of the channel but results in attenuation at lower frequencies. The voltage swing control and de-emphasis feature may be used together to optimally compensate for attenuation effects of the channel.

The frequency response of the PCB channel is typically lowpass with more attenuation occurring at higher frequencies. The de-emphasis implemented in the ADC31JB68 device is a form of linear, continuous-time equalization that shapes the signal at the transmitter into a high-pass response to counteract the low-pass response of the channel. The de-emphasis setting should be selected such that the equalizer’s frequency response is the inverse of the channel’s response. Therefore, transferring data at the highest speeds over long channel lengths requires knowledge of the channel characteristics.

Optimization of the de-emphasis and voltage swing settings is only necessary if the ISI and losses caused by the channel are too great for reception at the desired bit rate. Many applications will perform with an adequate BER using the default settings.