SLAS748F March   2011  – August 2015 DAC3482


  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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 Specifications
    6. 6.6  Electrical Characteristics - Digital Specifications
    7. 6.7  Electrical Characteristics - AC Specifications
    8. 6.8  Electrical Characteristics - Phase-Locked Loop Specifications
    9. 6.9  Timing Requirements - Digital Specifications
    10. 6.10 Switching Characteristics - AC Specifications
    11. 6.11 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Serial Interface
      2. 7.3.2  Data Interface
        1. Word-Wide Format
        2. Byte-Wide Format
      3. 7.3.3  Input FIFO
      4. 7.3.4  FIFO Modes of Operation
        1. Dual Sync Source Mode
        2. Single Sync Source Mode
        3. Bypass Mode
      5. 7.3.5  Clocking Modes
        1. PLL Bypass Mode
        2. PLL Mode
      6. 7.3.6  FIR Filters
      7. 7.3.7  Complex Signal Mixer
        1. Full Complex Mixer
        2. Coarse Complex Mixer
        3. Mixer Gain
        4. Real Channel Upconversion
      8. 7.3.8  Quadrature Modulation Correction (QMC)
        1. Gain and Phase Correction
        2. Offset Correction
        3. Group Delay Correction
      9. 7.3.9  Temperature Sensor
      10. 7.3.10 Data Pattern Checker
      11. 7.3.11 Parity Check Test
        1. Word-by-Word Parity
        2. Block Parity
      12. 7.3.12 DAC3482 Alarm Monitoring
      13. 7.3.13 LVPECL Inputs
      14. 7.3.14 LVDS Inputs
      15. 7.3.15 Unused LVDS Port Termination
      16. 7.3.16 CMOS Digital Inputs
      17. 7.3.17 Reference Operation
      18. 7.3.18 DAC Transfer Function
      19. 7.3.19 Analog Current Outputs
    4. 7.4 Device Functional Modes
      1. 7.4.1 Multi-Device Synchronization
        1. Multi-Device Synchronization: PLL Bypassed with Dual Sync Sources Mode
        2. Multi-Device Synchronization: PLL Enabled with Dual Sync Sources Mode
        3. Multi-Device Operation: Single Sync Source Mode
    5. 7.5 Programming
      1. 7.5.1 Power-Up Sequence
      2. 7.5.2 Example Start-Up Routine
        1. Device Configuration
        2. PLL Configuration
        3. NCO Configuration
        4. Example Start-Up Sequence
    6. 7.6 Register Map
      1. 7.6.1 Register Descriptions
        1.  Register Name: config0 - Address: 0x00, Default: 0x049C
        2.  Register Name: config1 - Address: 0x01, Default: 0x050E
        3.  Register Name: config2 - Address: 0x02, Default: 0x7000
        4.  Register Name: config3 - Address: 0x03, Default: 0xF000
        5.  Register Name: config4 - Address: 0x04, Default: No RESET Value (WRITE TO CLEAR)
        6.  Register Name: config5 - Address: 0x05, Default: Setup and Power-Up Conditions Dependent (WRITE TO CLEAR)
        7.  Register Name: config6 - Address: 0x06, Default: No RESET Value (READ ONLY)
        8.  Register Name: config7 - Address: 0x07, Default: 0xFFFF
        9.  Register Name: config8 - Address: 0x08, Default: 0x0000 (CAUSES AUTO-SYNC)
        10. Register Name: config9 - Address: 0x09, Default: 0x8000
        11. Register Name: config10 - Address: 0x0A, Default: 0x0000
        12. Register Name: config11 - Address: 0x0B, Default: 0x0000
        13. Register Name: config12 - Address: 0x0C, Default: 0x0400
        14. Register Name: config13 - Address: 0x0D, Default: 0x0400
        15. Register Name: config14 - Address: 0x0E, Default: 0x0400
        16. Register Name: config15 - Address: 0x0F, Default: 0x0400
        17. Register Name: config16 - Address: 0x10, Default: 0x0000 (CAUSES AUTO-SYNC)
        18. Register Name: config17 - Address: 0x11, Default: 0x0000
        19. Register Name: config18 - Address: 0x12, Default: 0x0000 (CAUSES AUTO-SYNC)
        20. Register Name: config19 - Address: 0x13, Default: 0x0000
        21. Register Name: config20 - Address: 0x14, Default: 0x0000
        22. Register Name: config21 - Address: 0x15, Default: 0x0000
        23. Register name: config22 - Address: 0x16, Default: 0x0000
        24. Register Name: config23 - Address: 0x17, Default: 0x0000
        25. Register Name: config24 - Address: 0x18, Default: NA
        26. Register Name: config25 - Address: 0x19, Default: 0x0440
        27. Register Name: config26 - Address: 0x1A, Default: 0x0020
        28. Register Name: config27 - Address: 0x1B, Default: 0x0000
        29. Register Name: config28 - Address: 0x1C, Default: 0x0000
        30. Register Name: config29 - Address: 0x1D, Default: 0x0000
        31. Register Name: config30 - Address: 0x1E, Default: 0x1111
        32. Register Name: config31 - Address: 0x1F, Default: 0x1140
        33. Register Name: config32 - Address: 0x20, Default: 0x2400
        34. Register Name: config33 - Address: 0x21, Default: 0x0000
        35. Register Name: config34 - Address: 0x22, Default: 0x1B1B
        36. Register Name: config35 - Address: 0x23, Default: 0xFFFF
        37. Register Name: config36 - Address: 0x24, Default: 0x0000
        38. Register Name: config37 - Address: 0x25, Default: 0x7A7A
        39. Register Name: config38 - Address: 0x26, Default: 0xB6B6
        40. Register Name: config39 - Address: 0x27, Default: 0xEAEA
        41. Register Name: config40 - Address: 0x28, Default: 0x4545
        42. Register Name: config41 - Address: 0x29, Default: 0x1A1A
        43. Register Name: config42 - Address: 0x2A, Default: 0x1616
        44. Register Name: config43 - Address: 0x2B, Default: 0xAAAA
        45. Register Name: config44 - Address: 0x2C, Default: 0xC6C6
        46. Register Name: config45 - Address: 0x2D, Default: 0x0004
        47. Register Name: config46 - Address: 0x2E, Default: 0x0000
        48. Register Name: config47 - Address: 0x2F, Default: 0x0000
        49. Register Name: config48 - Address: 0x30, Default: 0x0000
        50. Register Name: version- Address: 0x7F, Default: 0x540C (READ ONLY)
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 IF Based LTE Transmitter
        1. Design Requirements
        2. Detailed Design Procedure
          1. Data Input Rate
          2. Interpolation
          3. LO Feedthrough and Sideband Correction
        3. Application Curves
      2. 8.2.2 Direct Upconversion (Zero IF) LTE Transmitter
        1. Design Requirements
        2. Detailed Design Procedure
          1. Data Input Rate
          2. Interpolation
          3. LO Feedthrough and Sideband Correction
        3. Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
    3. 10.3 Assembly
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Device Nomenclature
        1. Definition of Specifications
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    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
    1. 12.1 Clarifications for DAC3482 Power Supply and Phase-Locked Loop Specification

Package Options

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

9 Power Supply Recommendations

As shown in Figure 99, the DAC3482 device has various power rails and has two primary voltages of 1.2 V and 3.3 V. Some of the DAC power rails such as CLKVDD and AVDD are more noise sensitive than other rails because they are mainly powering the switch drivers for the current switch array and the current bias circuits, respectively. These circuits are the main analog DAC core. Any power supply noises such as switching power supply ripple may be modulated directly onto the signal of interest. These two power rails should be powered by low noise power supplies such as LDO. Powering the rail directly with switching power supplies is not recommended for these two rails.

DAC3482 Power_desc_slas748.gifFigure 99. Interpolation Filters, NCOs, and QMC Blocks Powered by DIGVDD

With the DAC3482 being a mixed signal device, the device contains circuits that bridges the digital section and the analog section. The DACVDD powers these sections. System designer can design this rail in secondary priority. Powering the rail with LDO is recommended. Unless system designer pays special care to supply filtering and power supply routing/placement, powering the rail directly with switching power supplies is not recommended for this rail.

Since digital circuits have more inherent noise immunity than analog circuits, the power supply noise requirements for DIGVDD of the digital section of the device may be relaxed and placed at a lower priority. Depending on the spur level requirement, routing and placement of the power supply, power the rail directly with switching power supplies can be possible. With the digital logics running, the DIGVDD rail may draw significant current. If the power supply traces and filtering network have significant DC resistance loss (for example, DCR), then the final supply voltage seen by the DIGVDD rail may not be sufficient to meet the minimum power supply level. For instance, with 450 mA of DIGVDD current and about 0.1 Ω of DCR from the ferrite bead, the final supply voltage at the DIGVDD pins may be 1.2 V – 0.045 V = 1.155 V. This is fairly close to the minimum supply voltage range of 1.14 V. System designer may need to elevate the power supply voltage according to the DCR level or design a feedback network for the power supply to account for associated voltage drop. To ensure power supply accuracy and to account for power supply filter network loss at operating conditions, the use of the ATEST function in register config27 to check the internal power supply nodes is recommended.

The table below is a summary of the various power supply nodes of the DAC. Care should be taken to keep clean power supplies routing away from noisy digital supplies. It is recommended to use at least two power layers. Power supplies for digital circuits tend to have more switching activities and are typically noisier, and system designer should avoid sharing the digital power rail (for example, power supplies for FPGA or DIGVDD of DAC3482) with the analog power rail (for example, CLKVDD and AVDD of DAC3482). Avoid placing noisy supplies and clean supplies on adjacent board layers and use a ground layer between these two supplies if possible. All supply pins should be decoupled as close to the pins as possible by using small value capacitors, with larger bulk capacitors placed further away and near the power supply source.

Table 15. Power Rails

CLKVDD 1.2 V High Provide clean supply to the rail. Avoid spurious noise or coupling from other supplies High
AVDD 3.3 V High Provide clean supply to the rail. Avoid spurious noise or coupling from other supplies High
DACVDD 1.2 V Medium Provide clean supply to the rail. Avoid spurious noise or coupling from other supplies Medium
DIGVDD 1.2 V Low Keep Away from other noise sensitive nodes in placement and routing. Low