SNAS717A April   2017  – October 2021 ADC12D1620QML-SP

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  Converter Electrical Characteristics: Static Converter Characteristics
    6. 6.6  Converter Electrical Characteristics: Dynamic Converter Characteristics
    7. 6.7  Converter Electrical Characteristics: Analog Input/Output and Reference Characteristics
    8. 6.8  Converter Electrical Characteristic: Channel-to-Channel Characteristics
    9. 6.9  Converter Electrical Characteristics: LVDS CLK Input Characteristics
    10. 6.10 Electrical Characteristics: AutoSync Feature
    11. 6.11 Converter Electrical Characteristics: Digital Control and Output Pin Characteristics
    12. 6.12 Converter Electrical Characteristics: Power Supply Characteristics
    13. 6.13 Converter Electrical Characteristics: AC Electrical Characteristics
    14. 6.14 Electrical Characteristics: Delta Parameters
    15. 6.15 Timing Requirements: Serial Port Interface
    16. 6.16 Timing Requirements: Calibration
    17. 6.17 Quality Conformance Inspection
    18. 6.18 Timing Diagrams
    19. 6.19 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
      1. 7.1.1 Operation Summary
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Input Control and Adjust
        1. 7.3.1.1 AC- and DC-Coupled Modes
        2. 7.3.1.2 Input Full-Scale Range Adjust
        3. 7.3.1.3 Input Offset Adjust
        4. 7.3.1.4 Low-Sampling Power-Saving Mode (LSPSM)
        5. 7.3.1.5 DES Timing Adjust
        6. 7.3.1.6 Sampling Clock Phase Adjust
      2. 7.3.2 Output Control and Adjust
        1. 7.3.2.1 SDR / DDR Clock
        2. 7.3.2.2 LVDS Output Differential Voltage
        3. 7.3.2.3 LVDS Output Common-Mode Voltage
        4. 7.3.2.4 Output Formatting
        5. 7.3.2.5 Test-Pattern Mode
        6. 7.3.2.6 Time Stamp
      3. 7.3.3 Calibration Feature
        1. 7.3.3.1 Calibration Control Pins and Bits
        2. 7.3.3.2 How to Execute a Calibration
        3. 7.3.3.3 On-Command Calibration
        4. 7.3.3.4 Calibration Adjust
          1. 7.3.3.4.1 Read/Write Calibration Settings
        5. 7.3.3.5 Calibration and Power-Down
        6. 7.3.3.6 Calibration and the Digital Outputs
      4. 7.3.4 Power Down
      5. 7.3.5 Low-Sampling Power-Saving Mode (LSPSM)
    4. 7.4 Device Functional Modes
      1. 7.4.1 DES/Non-DES Mode
      2. 7.4.2 Demux/Non-Demux Mode
    5. 7.5 Programming
      1. 7.5.1 Control Modes
        1. 7.5.1.1 Non-ECM
          1. 7.5.1.1.1  Dual-Edge Sampling Pin (DES)
          2. 7.5.1.1.2  Non-Demultiplexed Mode Pin (NDM)
          3. 7.5.1.1.3  Dual Data-Rate Phase Pin (DDRPh)
          4. 7.5.1.1.4  Calibration Pin (CAL)
          5. 7.5.1.1.5  Low-Sampling Power-Saving Mode Pin (LSPSM)
          6. 7.5.1.1.6  Power-Down I-Channel Pin (PDI)
          7. 7.5.1.1.7  Power-Down Q-Channel Pin (PDQ)
          8. 7.5.1.1.8  Test-Pattern Mode Pin (TPM)
          9. 7.5.1.1.9  Full-Scale Input-Range Pin (FSR)
          10. 7.5.1.1.10 AC- or DC-Coupled Mode Pin (VCMO)
          11. 7.5.1.1.11 LVDS Output Common-Mode Pin (VBG)
        2. 7.5.1.2 Extended Control Mode
          1. 7.5.1.2.1 Serial Interface
    6. 7.6 Register Maps
      1. 7.6.1 Register Definitions
  8. 8 Application Information Disclaimer
    1. 8.1 Application Information
      1. 8.1.1 Analog Inputs
        1. 8.1.1.1 Acquiring the Input
        2. 8.1.1.2 Driving the ADC in DES Mode
        3. 8.1.1.3 FSR and the Reference Voltage
        4. 8.1.1.4 Out-Of-Range Indication
        5. 8.1.1.5 AC-Coupled Input Signals
        6. 8.1.1.6 DC-Coupled Input Signals
        7. 8.1.1.7 Single-Ended Input Signals
      2. 8.1.2 Clock Inputs
        1. 8.1.2.1 CLK Coupling
        2. 8.1.2.2 CLK Frequency
        3. 8.1.2.3 CLK Level
        4. 8.1.2.4 CLK Duty Cycle
        5. 8.1.2.5 CLK Jitter
        6. 8.1.2.6 CLK Layout
      3. 8.1.3 LVDS Outputs
        1. 8.1.3.1 Common-Mode and Differential Voltage
        2. 8.1.3.2 Output Data Rate
        3. 8.1.3.3 Terminating Unused LVDS Output Pins
      4. 8.1.4 Synchronizing Multiple ADC12D1620 Devices in a System
        1. 8.1.4.1 AutoSync Feature
        2. 8.1.4.2 DCLK Reset Feature
      5. 8.1.5 Temperature Sensor
    2. 8.2 Radiation Environments
      1. 8.2.1 Total Ionizing Dose
      2. 8.2.2 Single Event Latch-Up and Functional Interrupt
      3. 8.2.3 Single Event Upset
    3. 8.3 Cold Sparing
  9. 9 Power Supply Recommendations
    1. 9.1 System Power-On Considerations
      1. 9.1.1 Control Pins
      2. 9.1.2 Power On in Non-ECM
      3. 9.1.3 Power On in ECM
      4. 9.1.4 Power-on and Data Clock (DCLK)
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Power Planes
      2. 10.1.2 Bypass Capacitors
      3. 10.1.3 Ground Planes
      4. 10.1.4 Power System Example
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
    4. 10.4 Board Mounting Recommendation
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Device Nomenclature
      2. 11.1.2 Third-Party Products Disclaimer
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Engineering Samples

8.1.1.3 FSR and the Reference Voltage

The full-scale analog-differential input range (VIN_FSR) of the ADC12D1620 is derived from an internal bandgap reference. In Non-ECM, this full-scale range has two settings controlled by the FSR pin; see Full-Scale Input-Range Pin (FSR). The FSR Pin operates on both I and Q channels. In ECM, the full-scale range may be independently set with 15 bits of precision for each channel through the I- and Q-channel Full-Scale Range Adjust Registers (Addr: 3h and Addr: Bh, respectively); see Table 7-16 and Table 7-24 for information about the registers. The best SNR is obtained with a higher full-scale input range, but better distortion and SFDR are obtained with a lower full-scale input range. It is not possible to use an external analog reference voltage to modify the full-scale range, and this adjustment should only be done digitally, as described.

A buffered version of the internal bandgap reference voltage is made available at the VBG pin for the user. The VBG pin can drive a load of up to 80-pF and source or sink up to 100 μA. It must be buffered if current higher than 100 μA is required. This pin remains as a constant reference voltage regardless of what full-scale range is selected and may be used for a system reference. VBG is a dual-purpose pin and it may also be used to select a higher LVDS output common-mode voltage; see LVDS Output Common-Mode Pin (VBG).