SBASAP4 April   2025 ADC3664-EP , ADC3664-SEP

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 - Power Consumption
    6. 5.6 Electrical Characteristics - DC Specifications
    7. 5.7 Electrical Characteristics - AC Specifications
    8. 5.8 Timing Requirements
    9. 5.9 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Analog Input
        1. 7.3.1.1 Analog Input Bandwidth
        2. 7.3.1.2 Analog Front End Design
          1. 7.3.1.2.1 Sampling Glitch Filter Design
          2. 7.3.1.2.2 Analog Input Termination and DC Bias
            1. 7.3.1.2.2.1 AC-Coupling
            2. 7.3.1.2.2.2 DC-Coupling
      2. 7.3.2 Clock Input
        1. 7.3.2.1 Single Ended vs Differential Clock Input
      3. 7.3.3 Voltage Reference
        1. 7.3.3.1 Internal voltage reference
        2. 7.3.3.2 External voltage reference (VREF)
        3. 7.3.3.3 External voltage reference with internal buffer (REFBUF/CTRL)
      4. 7.3.4 Digital Down Converter
        1. 7.3.4.1 DDC MUX
        2. 7.3.4.2 Digital Filter Operation
        3. 7.3.4.3 FS/4 Mixing with Real Output
        4. 7.3.4.4 Numerically Controlled Oscillator (NCO) and Digital Mixer
        5. 7.3.4.5 Decimation Filter
        6. 7.3.4.6 SYNC
        7. 7.3.4.7 Output Formatting with Decimation
      5. 7.3.5 Digital Interface
        1. 7.3.5.1 Output Formatter
        2. 7.3.5.2 Output Bit Mapper
          1. 7.3.5.2.1 2-Wire Mode
          2. 7.3.5.2.2 1-Wire Mode
          3. 7.3.5.2.3 ½-Wire Mode
        3. 7.3.5.3 Output Interface and Mode Configuration
          1. 7.3.5.3.1 Configuration Example
        4. 7.3.5.4 Output Data Format
      6. 7.3.6 Test Pattern
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal operation
      2. 7.4.2 Power Down Options
    5. 7.5 Programming
      1. 7.5.1 Configuration using PINs only
      2. 7.5.2 Configuration using the SPI interface
        1. 7.5.2.1 Register Write
        2. 7.5.2.2 Register Read
  9. 8 Application Information Disclaimer
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Input Signal Path
        2. 8.2.2.2 Sampling Clock
        3. 8.2.2.3 Voltage Reference
      3. 8.2.3 Application Curves
    3. 8.3 Initialization Set Up
      1. 8.3.1 Register Initialization During Operation
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  10. 9 Register Maps
    1. 9.1 Detailed Register Description
  11. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Mechanical Data

7.3.3 Voltage Reference

The ADC3664-xEP provides three different options for supplying the voltage reference to the ADC. An external 1.6V reference is directly connected to the VREF input; a voltage 1.2V reference is connected to the REFBUF/CTRL input using the internal gain buffer or the internal 1.2V reference is enabled to generate a 1.6V reference voltage. For best performance, the reference noise should be filtered by connecting a 10μF and a 0.1μF ceramic bypass capacitor to the VREF pin. The internal reference circuitry of the ADC3664-xEP is shown in Figure 7-11.

Note: The voltage reference mode is selected using SPI writes or by using the REFBUF/CTRL pin (default) as a control pin (Section 7.5.1). If the REFBUF/CTRL pin is not used for configuration, the REFBUF/CTRL pin should be connected to AVDD (even though the REFBUF/CTRL pin has a weak internal pullup to AVDD) and the voltage reference option has to be selected using the SPI interface.

ADC3664-SEP ADC3664-EP Different voltage reference options for ADC3664-xEPFigure 7-11 Different voltage reference options for ADC3664-xEP