SLVSEO1A August   2021  – May 2022 ADC08DJ5200RF

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: DC Specifications
    6. 6.6  Electrical Characteristics: Power Consumption
    7. 6.7  Electrical Characteristics: AC Specifications (Dual-Channel Mode)
    8. 6.8  Electrical Characteristics: AC Specifications (Single-Channel Mode)
    9. 6.9  Timing Requirements
    10. 6.10 Switching Characteristics
    11. 6.11 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Comparison
      2. 7.3.2 Analog Inputs
        1. 7.3.2.1 Analog Input Protection
        2. 7.3.2.2 Full-Scale Voltage (VFS) Adjustment
        3. 7.3.2.3 Analog Input Offset Adjust
      3. 7.3.3 ADC Core
        1. 7.3.3.1 ADC Theory of Operation
        2. 7.3.3.2 ADC Core Calibration
        3. 7.3.3.3 Analog Reference Voltage
        4. 7.3.3.4 ADC Overrange Detection
        5. 7.3.3.5 Code Error Rate (CER)
      4. 7.3.4 Temperature Monitoring Diode
      5. 7.3.5 Timestamp
      6. 7.3.6 Clocking
        1. 7.3.6.1 Noiseless Aperture Delay Adjustment (tAD Adjust)
        2. 7.3.6.2 Aperture Delay Ramp Control (TAD_RAMP)
        3. 7.3.6.3 SYSREF Capture for Multi-Device Synchronization and Deterministic Latency
          1. 7.3.6.3.1 SYSREF Position Detector and Sampling Position Selection (SYSREF Windowing)
          2. 7.3.6.3.2 Automatic SYSREF Calibration
      7. 7.3.7 Programmable FIR Filter (PFIR)
        1. 7.3.7.1 Dual Channel Equalization
        2. 7.3.7.2 Single Channel Equalization
        3. 7.3.7.3 Time Varying Filter
      8. 7.3.8 JESD204C Interface
        1. 7.3.8.1 Transport Layer
        2. 7.3.8.2 Scrambler
        3. 7.3.8.3 Link Layer
        4. 7.3.8.4 8B/10B Link Layer
          1. 7.3.8.4.1 Data Encoding (8B/10B)
          2. 7.3.8.4.2 Multiframes and the Local Multiframe Clock (LMFC)
          3. 7.3.8.4.3 Code Group Synchronization (CGS)
          4. 7.3.8.4.4 Initial Lane Alignment Sequence (ILAS)
          5. 7.3.8.4.5 Frame and Multiframe Monitoring
        5. 7.3.8.5 64B/66B Link Layer
          1. 7.3.8.5.1 64B/66B Encoding
          2. 7.3.8.5.2 Multiblocks, Extended Multiblocks and the Local Extended Multiblock Clock (LEMC)
          3. 7.3.8.5.3 Block, Multiblock and Extended Multiblock Alignment using Sync Header
            1. 7.3.8.5.3.1 Cyclic Redundancy Check (CRC) Mode
            2. 7.3.8.5.3.2 Forward Error Correction (FEC) Mode
          4. 7.3.8.5.4 Initial Lane Alignment
          5. 7.3.8.5.5 Block, Multiblock and Extended Multiblock Alignment Monitoring
        6. 7.3.8.6 Physical Layer
          1. 7.3.8.6.1 SerDes Pre-Emphasis
        7. 7.3.8.7 JESD204C Enable
        8. 7.3.8.8 Multi-Device Synchronization and Deterministic Latency
        9. 7.3.8.9 Operation in Subclass 0 Systems
      9. 7.3.9 Alarm Monitoring
        1. 7.3.9.1 Clock Upset Detection
        2. 7.3.9.2 FIFO Upset Detection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Dual-Channel Mode
      2. 7.4.2 Single-Channel Mode (DES Mode)
      3. 7.4.3 Dual-Input Single-Channel Mode (DUAL DES Mode)
      4. 7.4.4 JESD204C Modes
        1. 7.4.4.1 JESD204C Operating Modes Table
        2. 7.4.4.2 JESD204C Modes continued
        3. 7.4.4.3 JESD204C Transport Layer Data Formats
        4. 7.4.4.4 64B/66B Sync Header Stream Configuration
      5. 7.4.5 Power-Down Modes
      6. 7.4.6 Test Modes
        1. 7.4.6.1 Serializer Test-Mode Details
        2. 7.4.6.2 PRBS Test Modes
        3. 7.4.6.3 Clock Pattern Mode
        4. 7.4.6.4 Ramp Test Mode
        5. 7.4.6.5 Short and Long Transport Test Mode
          1. 7.4.6.5.1 Short Transport Test Pattern
        6. 7.4.6.6 D21.5 Test Mode
        7. 7.4.6.7 K28.5 Test Mode
        8. 7.4.6.8 Repeated ILA Test Mode
        9. 7.4.6.9 Modified RPAT Test Mode
      7. 7.4.7 Calibration Modes and Trimming
        1. 7.4.7.1 Foreground Calibration Mode
        2. 7.4.7.2 Background Calibration Mode
        3. 7.4.7.3 Low-Power Background Calibration (LPBG) Mode
      8. 7.4.8 Offset Calibration
      9. 7.4.9 Trimming
    5. 7.5 Programming
      1. 7.5.1 Using the Serial Interface
        1. 7.5.1.1 SCS
        2. 7.5.1.2 SCLK
        3. 7.5.1.3 SDI
        4. 7.5.1.4 SDO
        5. 7.5.1.5 Streaming Mode
    6. 7.6 SPI Register Map
  8. 8 Application Information Disclaimer
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Reconfigurable Dual-Channel 5-GSPS or Single-Channel 10-Gsps Oscilloscope
        1. 8.2.1.1 Design Requirements
          1. 8.2.1.1.1 Input Signal Path
          2. 8.2.1.1.2 Clocking
          3. 8.2.1.1.3 ADC08DJ5200RF
    3. 8.3 Initialization Set Up
  9. 9 Power Supply Recommendations
    1. 9.1 Power Sequencing
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 123
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

7.3.3.4 ADC Overrange Detection

To make sure that system gain management has the quickest possible response time, a low-latency configurable overrange function is included. The overrange function works by monitoring the converted samples at the ADC to quickly detect if the ADC is near saturation or already in an overrange condition. The absolute value of the ADC data are checked against two programmable thresholds, OVR_T0 and OVR_T1. These thresholds apply to both channel A and channel B in dual-channel mode. Table 7-2 lists how an ADC sample is converted to an absolute value for a comparison of the thresholds.

Table 7-2 Conversion of ADC Sample for Overrange Comparison
ADC SAMPLE
(Offset Binary)		 ADC SAMPLE
(2's Complement)		 ABSOLUTE VALUE
1111 1111 (255) 0111 1111(+127) 111 1111 (127)
1111 0000 (240) 0111 0000 (+112) 111 0000 (112)
1000 0000 (128) 0000 0000 (0) 0000 0000(0)
0001 0000 (16) 1000 0001 0000 (–112) 111 0000 (112)
0000 0000 (0) 1000 0000 0000 (–128) 111 1111 (127)

If the absolute value equal or exceed the OVR_T0 or OVR_T1 thresholds during the monitoring period, then the overrange bit associated with the threshold is set to 1, otherwise the overrange bit is 0. In dual-channel mode, the overrange status can be monitored on the ORA0 and ORA1 pins for channel A and the ORB0 and ORB1 pins for channel B, where ORx0 corresponds to the OVR_T0 threshold and ORx1 corresponds to the OVR_T1 threshold. In single-channel mode, the overrange status for the OVR_T0 threshold is determined by monitoring both the ORA0 and ORB0 outputs and the OVR_T1 threshold is determined by monitoring both ORA1 and ORB1 outputs. In single-channel mode, the two outputs for each threshold must be OR'd together to determine whether an overrange condition occurred. OVR_N can be used to set the output pulse duration from the last overrange event. Table 7-3 lists the overrange pulse lengths for the various OVR_N settings.

Table 7-3 Overrange Monitoring Period for the ORA0, ORA1, ORB0, and ORB1 Outputs
OVR_NOVERRANGE PULSE LENGTH SINCE LAST OVERRANGE EVENT (DEVCLK Cycles)
08
116
232
364
4128
5256
6512
71024

Typically, the OVR_T0 threshold can be set near the full-scale value (228 for example). When the threshold is triggered, a typical system can turn down the system gain to avoid clipping. The OVR_T1 threshold can be set much lower. For example, the OVR_T1 threshold can be set to 64 (peak input voltage of −12 dBFS). If the input signal is strong, the OVR_T1 threshold is tripped occasionally. If the input is quite weak, the threshold is never tripped. The downstream logic device monitors the OVR_T1 bit. If OVR_T1 stays low for an extended period of time, then the system gain can be increased until the threshold is occasionally tripped (meaning the peak level of the signal is above −12 dBFS).