SBASAU7C December   2024  – July 2025 ADC3548 , ADC3549

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Device Comparison
  6. Pin Configuration and Functions
  7. 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 - Power Consumption
    6. 6.6  Electrical Characteristics - DC Specifications
    7. 6.7  Electrical Characteristics - AC Specifications (ADC3548 - 250 MSPS)
    8. 6.8  Electrical Characteristics - AC Specifications (ADC3549 - 500 MSPS)
    9. 6.9  Timing Requirements
    10. 6.10 Typical Characteristics - ADC3548 (250MSPS)
    11. 6.11 Typical Characteristics - ADC3549 (500MSPS)
  8. Parameter Measurement Information
  9. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Analog Inputs
        1. 8.3.1.1 Nyquist Zone Selection
        2. 8.3.1.2 Analog Front End Design
      2. 8.3.2 Sampling Clock
        1. 8.3.2.1 Multi-Chip Synchronization
        2. 8.3.2.2 SYSREF Monitor
      3. 8.3.3 Time-Stamp
      4. 8.3.4 Overrange
      5. 8.3.5 External Voltage Reference
      6. 8.3.6 Digital Gain
      7. 8.3.7 Decimation Filter
        1. 8.3.7.1 Uncommon Decimation Ratios
        2. 8.3.7.2 Decimation Filter Response
        3. 8.3.7.3 Decimation Filter Configuration
        4. 8.3.7.4 Numerically Controlled Oscillator (NCO)
      8. 8.3.8 Digital Interface
        1. 8.3.8.1 Parallel LVDS (SDR) - Default
        2. 8.3.8.2 Parallel LVDS (DDR)
        3. 8.3.8.3 SLVDS with Decimation
          1. 8.3.8.3.1 SLVDS - Status Bit Insertion
        4. 8.3.8.4 Output Data Format
        5. 8.3.8.5 32-bit Output Resolution
        6. 8.3.8.6 Output Scrambler
        7. 8.3.8.7 Output MUX
        8. 8.3.8.8 Test Pattern
    4. 8.4 Device Functional Modes
      1. 8.4.1 Low Latency Mode
      2. 8.4.2 Power Down Mode
    5. 8.5 Programming
      1. 8.5.1 GPIO Programming
      2. 8.5.2 Register Write
      3. 8.5.3 Register Read
      4. 8.5.4 Device Programming
      5. 8.5.5 Register Map
      6. 8.5.6 Register Description
  10. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Wideband Spectrum Analyzer
      2. 9.2.2 Design Requirements
        1. 9.2.2.1 Input Signal Path
        2. 9.2.2.2 Clocking
      3. 9.2.3 Detailed Design Procedure
        1. 9.2.3.1 Sampling Clock
      4. 9.2.4 Application Performance Plots
      5. 9.2.5 Initialization Set Up
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Third-Party Products Disclaimer
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

Analog Inputs

The analog inputs of the ADC366x have internal buffers which isolate the sampling capacitor glitch noise from the external input circuitry. The analog inputs have a differential 100Ω split termination with internal biasing to VCM as illustrated in the representative input model in Figure 8-2. This can be changed to differential 200Ω termination via SPI register write.

The input fullscale is 2Vpp and the VCM is 1.4V; thus, the voltage on the analog inputs swing between 0.9V and 1.9V. The ADC inputs are reliably designed to support 1.9V for normal operation.

ADC3548 ADC3549 Analog input internal
            terminationFigure 8-2 Analog input internal termination
ADC3548 ADC3549 Analog input voltage rangeFigure 8-3 Analog input voltage range

The device supports both AC and DC coupling of the analog inputs as shown in Figure 8-4 and Figure 8-5.

ADC3548 ADC3549 AC
                                                  couplingFigure 8-4 AC coupling
ADC3548 ADC3549 DC
                                                  couplingFigure 8-5 DC coupling

The input bandwidth (-3 dB) for internal 100Ω and 200Ω termination are shown in Figure 8-6.

ADC3548 ADC3549 Full power input bandwidth for 100Ω
          and 200Ω internal termination Figure 8-6 Full power input bandwidth for 100Ω and 200Ω internal termination