SBASA52A July   2021  – October 2024 ADC12DJ800-Q1 , ADC12QJ800-Q1 , ADC12SJ800-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  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: DC Specifications
    6. 5.6  Electrical Characteristics: Power Consumption
    7. 5.7  Electrical Characteristics: AC Specifications
    8. 5.8  Timing Requirements
    9. 5.9  Switching Characteristics
    10. 5.10 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Device Comparison
      2. 6.3.2 Analog Input
        1. 6.3.2.1 Analog Input Protection
        2. 6.3.2.2 Full-Scale Voltage (VFS) Adjustment
        3. 6.3.2.3 Analog Input Offset Adjust
        4. 6.3.2.4 ADC Core
          1. 6.3.2.4.1 ADC Theory of Operation
          2. 6.3.2.4.2 ADC Core Calibration
          3. 6.3.2.4.3 Analog Reference Voltage
          4. 6.3.2.4.4 ADC Over-range Detection
          5. 6.3.2.4.5 Code Error Rate (CER)
      3. 6.3.3 Temperature Monitoring Diode
      4. 6.3.4 Timestamp
      5. 6.3.5 Clocking
        1. 6.3.5.1 Converter PLL (C-PLL) for Sampling Clock Generation
        2. 6.3.5.2 LVDS Clock Outputs (PLLREFO±, TRIGOUT±)
        3. 6.3.5.3 Optional CMOS Clock Outputs (ORC, ORD)
        4. 6.3.5.4 SYSREF for JESD204C Subclass-1 Deterministic Latency
          1. 6.3.5.4.1 SYSREF Capture for Multi-Device Synchronization and Deterministic Latency
          2. 6.3.5.4.2 SYSREF Position Detector and Sampling Position Selection (SYSREF Windowing)
      6. 6.3.6 JESD204C Interface
        1. 6.3.6.1  Transport Layer
        2. 6.3.6.2  Scrambler
        3. 6.3.6.3  Link Layer
        4. 6.3.6.4  8B/10B Link Layer
          1. 6.3.6.4.1 Data Encoding (8B/10B)
          2. 6.3.6.4.2 Multiframes and the Local Multiframe Clock (LMFC)
          3. 6.3.6.4.3 Code Group Synchronization (CGS)
          4. 6.3.6.4.4 Initial Lane Alignment Sequence (ILAS)
          5. 6.3.6.4.5 Frame and Multiframe Monitoring
        5. 6.3.6.5  64B/66B Link Layer
          1. 6.3.6.5.1 64B/66B Encoding
          2. 6.3.6.5.2 Multiblocks, Extended Multiblocks and the Local Extended Multiblock Clock (LEMC)
            1. 6.3.6.5.2.1 Block, Multiblock and Extended Multiblock Alignment using Sync Header
              1. 6.3.6.5.2.1.1 Cyclic Redundancy Check (CRC) Mode
              2. 6.3.6.5.2.1.2 Forward Error Correction (FEC) Mode
          3. 6.3.6.5.3 Initial Lane Alignment
          4. 6.3.6.5.4 Block, Multiblock and Extended Multiblock Alignment Monitoring
        6. 6.3.6.6  Physical Layer
          1. 6.3.6.6.1 SerDes Pre-Emphasis
        7. 6.3.6.7  JESD204C Enable
        8. 6.3.6.8  Multi-Device Synchronization and Deterministic Latency
        9. 6.3.6.9  Operation in Subclass 0 Systems
        10. 6.3.6.10 Alarm Monitoring
          1. 6.3.6.10.1 Clock Upset Detection
          2. 6.3.6.10.2 FIFO Upset Detection
    4. 6.4 Device Functional Modes
      1. 6.4.1 Low Power Mode and High Performance Mode
      2. 6.4.2 JESD204C Modes
        1. 6.4.2.1 JESD204C Transport Layer Data Formats
        2. 6.4.2.2 64B/66B Sync Header Stream Configuration
        3. 6.4.2.3 Redundant Data Mode (Alternate Lanes)
      3. 6.4.3 Power-Down Modes
      4. 6.4.4 Test Modes
        1. 6.4.4.1 Serializer Test-Mode Details
        2. 6.4.4.2 PRBS Test Modes
        3. 6.4.4.3 Clock Pattern Mode
        4. 6.4.4.4 Ramp Test Mode
        5. 6.4.4.5 Short and Long Transport Test Mode
          1. 6.4.4.5.1 Short Transport Test Pattern
        6. 6.4.4.6 D21.5 Test Mode
        7. 6.4.4.7 K28.5 Test Mode
        8. 6.4.4.8 Repeated ILA Test Mode
        9. 6.4.4.9 Modified RPAT Test Mode
      5. 6.4.5 Calibration Modes and Trimming
        1. 6.4.5.1 Foreground Calibration Mode
        2. 6.4.5.2 Background Calibration Mode
        3. 6.4.5.3 Low-Power Background Calibration (LPBG) Mode
      6. 6.4.6 Offset Calibration
      7. 6.4.7 Trimming
    5. 6.5 Programming
      1. 6.5.1 Using the Serial Interface
      2. 6.5.2 SCS
      3. 6.5.3 SCLK
      4. 6.5.4 SDI
      5. 6.5.5 SDO
      6. 6.5.6 Streaming Mode
      7. 6.5.7 SPI_Register_Map Registers
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Light Detection and Ranging (LiDAR) Digitizer
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
          1. 7.2.1.2.1 Analog Front-End Requirements
          2. 7.2.1.2.2 Calculating Clock and SerDes Frequencies
        3. 7.2.1.3 Application Curves
    3. 7.3 Initialization Set Up
    4. 7.4 Power Supply Recommendations
      1. 7.4.1 Power Sequencing
    5. 7.5 Layout
      1. 7.5.1 Layout Guidelines
      2. 7.5.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

6.4.6 Offset Calibration

Foreground calibration and background calibration modes inherently calibrate the offsets of the ADC cores; however, the input buffers sit outside of the calibration loop and therefore their offsets are not calibrated by the standard calibration process. A separate calibration is provided to correct the input buffer offsets.

There must be no signals at or near DC or aliased signals that fall at or near DC in order to properly calibration the offsets, requiring the system to specify this condition during normal operation or have the ability to mute the input signal during calibration. Foreground offset calibration is enabled via CAL_OS and only performs the calibration one time as part of the foreground calibration procedure. Background offset calibration is enabled via CAL_BGOS and continues to correct the offset as part of the background calibration routine to account for operating condition changes. When CAL_BGOS is set, the system must make sure that there are no DC or near DC signals or aliased signals that fall at or near DC during normal operation. Offset calibration can be performed as a foreground operation when using background calibration by setting CAL_OS to 1 before setting CAL_EN, but does not correct for variations as operating conditions change.

The offset calibration correction uses the input offset voltage trim registers (see OFS0 to OFS5) to correct the offset and therefore must not be written by the user when offset calibration is used. The user can read the calibrated values by reading the offset trim registers after calibration is completed and then use these values in the future to overwrite the factory trim values. Only read the values when FG_DONE is read as 1 when using foreground offset calibration (CAL_OS = 1) and do not read the values when using background offset calibration (CAL_BGOS = 1). Setting CAL_OS to 1 and CAL_BG to 1 performs an offset calibration of all six cores during the foreground calibration process.

Some systems, such as pulsed input systems, may purposefully apply a large external DC offset to the analog inputs to maximize the dynamic range for uni-polar signals. Standard offset calibration does not work for these systems because of the applied DC offset. These systems can instead set OSREF to use the spare ADC as the offset reference and then calibrate the main ADC cores to match the spare offset. This allows seamless offset transitions during background calibration swapping.