SBASAT9 February   2024 ADC12DL1500 , ADC12DL2500 , ADC12DL500

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 (Dual-Channel Mode)
    8. 5.8  Electrical Characteristics: AC Specifications (Single-Channel Mode)
    9. 5.9  Timing Requirements
    10. 5.10 Switching Characteristics
    11. 5.11 Timing Diagrams
    12. 5.12 Typical Characteristics - ADC12DL500
    13. 5.13 Typical Characteristics - ADC12DL1500 (1GSPS)
    14. 5.14 Typical Characteristics - ADC12DL1500 (1.5GSPS)
    15. 5.15 Typical Characteristics - ADC12DL2500 (2GSPS)
    16. 5.16 Typical Characteristics - ADC12DL2500 (2.5GSPS)
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Analog Inputs
        1. 6.3.1.1 Analog Input Protection
        2. 6.3.1.2 Full-Scale Voltage (VFS) Adjustment
        3. 6.3.1.3 Analog Input Offset Adjust
      2. 6.3.2 ADC Core
        1. 6.3.2.1 ADC Theory of Operation
        2. 6.3.2.2 ADC Core Calibration
        3. 6.3.2.3 ADC Overrange Detection
        4. 6.3.2.4 Code Error Rate (CER)
        5. 6.3.2.5 Internal Dither
      3. 6.3.3 Timestamp
      4. 6.3.4 Clocking
        1. 6.3.4.1 Noiseless Aperture Delay Adjustment (tAD Adjust)
        2. 6.3.4.2 Aperture Delay Ramp Control (TAD_RAMP)
        3. 6.3.4.3 SYSREF Capture for Multi-Device Synchronization and Deterministic Latency
          1. 6.3.4.3.1 SYSREF Position Detector and Sampling Position Selection (SYSREF Windowing)
          2. 6.3.4.3.2 Automatic SYSREF Calibration
      5. 6.3.5 LVDS Digital Interface
        1. 6.3.5.1 Multi-Device Synchronization and Deterministic Latency Using Strobes
          1. 6.3.5.1.1 Dedicated Strobe Pins
          2. 6.3.5.1.2 Reduced Width Interface With Dedicated Strobe Pins
          3. 6.3.5.1.3 LSB Replacement With a Strobe
          4. 6.3.5.1.4 Strobe Over All Data Pairs
      6. 6.3.6 Alarm Monitoring
        1. 6.3.6.1 Clock Upset Detection
      7. 6.3.7 Temperature Monitoring Diode
      8. 6.3.8 Analog Reference Voltage
    4. 6.4 Device Functional Modes
      1. 6.4.1 Dual-Channel Mode (Non-DES Mode)
      2. 6.4.2 Internal Dither Modes
      3. 6.4.3 Single-Channel Mode (DES Mode)
      4. 6.4.4 LVDS Output Driver Modes
      5. 6.4.5 LVDS Output Modes
        1. 6.4.5.1 Staggered Output Mode
        2. 6.4.5.2 Aligned Output Mode
        3. 6.4.5.3 Reducing the Number of Strobes
        4. 6.4.5.4 Reducing the Number of Data Clocks
        5. 6.4.5.5 Scrambling
        6. 6.4.5.6 Digital Interface Test Patterns and LVSD SYNC Functionality
          1. 6.4.5.6.1 Active Pattern
          2. 6.4.5.6.2 Synchronization Pattern
          3. 6.4.5.6.3 User-Defined Test Pattern
      6. 6.4.6 Power-Down Modes
      7. 6.4.7 Calibration Modes and Trimming
        1. 6.4.7.1 Foreground Calibration Mode
      8. 6.4.8 Offset Calibration
      9. 6.4.9 Trimming
    5. 6.5 Programming
      1. 6.5.1 Using the Serial Interface
        1. 6.5.1.1 SCS
        2. 6.5.1.2 SCLK
        3. 6.5.1.3 SDI
        4. 6.5.1.4 SDO
        5. 6.5.1.5 80
        6. 6.5.1.6 Streaming Mode
        7. 6.5.1.7 82
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Reconfigurable Dual-Channel 2.5GSPS or Single-Channel 5GSPS Oscilloscope
        1. 7.2.1.1 Design Requirements
          1. 7.2.1.1.1 Input Signal Path
          2. 7.2.1.1.2 Clocking
          3. 7.2.1.1.3 ADC12DLx500
        2. 7.2.1.2 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 Register Maps
    1. 8.1 SPI_REGISTER_MAP Registers
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
7.2.1.1.1 Input Signal Path

Most oscilloscopes are required to be DC-coupled to monitor DC or low-frequency signals. This requirement forces the design to use DC-coupled, fully differential amplifiers to convert from single-ended signaling at the front panel to differential signaling at the ADC. This design uses two differential amplifiers. The first amplifier shown in Figure 7-1 is the LMH5401 that converts from single-ended to differential signaling. The LMH5401 interfaces with the front panel through a programmable termination network and has an offset adjustment input. The amplifier has an 8GHz, gain-bandwidth product that is sufficient to support a 1-GHz bandwidth oscilloscope. A second amplifier, the LMH6401, comes after the LMH5401 to provide a digitally programmable gain control for the oscilloscope. The LMH6401 supports a gain range from –6dB to 26dB in 1dB steps. If gain control is not necessary or is performed in a different location in the signal chain, then this amplifier can be replaced with a second LMH5401 for additional fixed gain or omitted altogether.

The input of the oscilloscope contains a programmable termination block that is not covered in detail here. This block enables the front-panel input termination to be programmed. For instance, many oscilloscopes allow the termination to be programmed as either 50Ω or 1MΩ to meet the needs of various applications. A 75Ω termination can also be desired to support cable infrastructure use cases. This block can also contain an option for DC blocking to remove the DC component of the external signal and therefore pass only AC signals.

A precision digital-to-analog converter (DAC) is used to configure the offset of the oscilloscope front-end to prevent saturation of the analog signal chain for input signals containing large DC offsets. The DAC8560 is shown in Figure 7-1 along with signal-conditioning amplifiers OPA703 and LMH6559. The first differential amplifier, LMH5401, is driven by the front panel input circuitry on one input, and the DC offset bias on the second input. The impedance of these driving signals must be matched at DC and over frequency for good even-order harmonic performance in the single-ended to differential conversion operation. The high bandwidth of the LMH6559 allows the device to maintain low impedance over a wide frequency range.

An antialiasing, low-pass filter is positioned at the input of the ADC to limit the bandwidth of the input signal into the ADC. This amplifier also band-limits the front-end noise to prevent aliased noise from degrading the signal-to-noise ratio of the overall system. Design this filter for the maximum input signal bandwidth specified by the oscilloscope. The input bandwidth can then be reconfigured through the use of digital filters in the FPGA or ASIC to limit the oscilloscope input bandwidth to a bandwidth less than the maximum.