SLAS535F September   2007  – October 2018 DAC5652A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
    1.     Functional Block Diagram
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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
    6. 6.6  Electrical Characteristics: AC
    7. 6.7  Electrical Characteristics: Digital Input
    8. 6.8  Electrical Characteristics: Power Supply
    9. 6.9  Switching Characteristics
    10. 6.10 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 Digital Inputs
      2. 7.3.2 References
        1. 7.3.2.1 Internal Reference
        2. 7.3.2.2 External Reference
    4. 7.4 Device Functional Modes
      1. 7.4.1 Input Interfaces
        1. 7.4.1.1 Dual-Bus Data Interface and Timing
        2. 7.4.1.2 Single-Bus Interleaved Data Interface and Timing
      2. 7.4.2 Gain Setting Option
      3. 7.4.3 Sleep Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 DAC Transfer Function
        1. 8.1.1.1 Analog Outputs
      2. 8.1.2 Output Configurations
      3. 8.1.3 Differential With Transformer
      4. 8.1.4 Single-Ended Configuration
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

8.1.1.1 Analog Outputs

The DAC5652A provides two complementary current outputs, IOUT1 and IOUT2. The simplified circuit of the analog output stage representing the differential topology is shown in Figure 17. The output impedance of IOUT1 and IOUT2 results from the parallel combination of the differential switches, along with the current sources and associated parasitic capacitances.

DAC5652A analogout_las452.gifFigure 17. Analog Outputs

The signal voltage swing that may develop at the two outputs, IOUT1 and IOUT2, is limited by a negative and positive compliance. The negative limit of –1 V is given by the breakdown voltage of the CMOS process and exceeding it compromises the reliability of the DAC5652A (or even causes permanent damage). With the full-scale output set to 20 mA, the positive compliance equals 1.2 V. Note that the compliance range decreases to about 1 V for a selected output current of I(OUTFS) = 2 mA. Care must be taken that the configuration of DAC5652A does not exceed the compliance range to avoid degradation of the distortion performance and integral linearity.

Best distortion performance is typically achieved with the maximum full-scale output signal limited to approximately 0.5 VPP. This is the case for a 50-Ω doubly-terminated load and a 20-mA full-scale output current. A variety of loads can be adapted to the output of the DAC5652A by selecting a suitable transformer while maintaining optimum voltage levels at IOUT1 and IOUT2. Furthermore, using the differential output configuration in combination with a transformer is instrumental for achieving excellent distortion performance. Common-mode errors, such as even-order harmonics or noise, can be substantially reduced. This is particularly the case with high output frequencies.

For those applications requiring the optimum distortion and noise performance, it is recommended to select a full-scale output of 20 mA. A lower full-scale range of 2 mA may be considered for applications that require low power consumption, but can tolerate a slight reduction in performance level.