SLAS748G March   2011  β€“ January 2024 DAC3482

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 – Digital Specifications
    7. 5.7  Electrical Characteristics – AC Specifications
    8. 5.8  Electrical Characteristics - Phase-Locked Loop Specifications
    9. 5.9  Timing Requirements - Digital Specifications
    10. 5.10 Switching Characteristics – AC Specifications
    11. 5.11 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Serial Interface
      2. 6.3.2  Data Interface
        1. 6.3.2.1 Word-Wide Format
        2. 6.3.2.2 Byte-Wide Format
      3. 6.3.3  Input FIFO
      4. 6.3.4  FIFO Modes of Operation
        1. 6.3.4.1 Dual Sync Source Mode
        2. 6.3.4.2 Single Sync Source Mode
        3. 6.3.4.3 Bypass Mode
      5. 6.3.5  Clocking Modes
        1. 6.3.5.1 PLL Bypass Mode
        2. 6.3.5.2 PLL Mode
      6. 6.3.6  FIR Filters
      7. 6.3.7  Complex Signal Mixer
        1. 6.3.7.1 Full Complex Mixer
        2. 6.3.7.2 Coarse Complex Mixer
        3. 6.3.7.3 Mixer Gain
        4. 6.3.7.4 Real Channel Upconversion
      8. 6.3.8  Quadrature Modulation Correction (QMC)
        1. 6.3.8.1 Gain and Phase Correction
        2. 6.3.8.2 Offset Correction
        3. 6.3.8.3 Group Delay Correction
      9. 6.3.9  Temperature Sensor
      10. 6.3.10 Data Pattern Checker
      11. 6.3.11 Parity Check Test
        1. 6.3.11.1 Word-by-Word Parity
        2. 6.3.11.2 Block Parity
      12. 6.3.12 DAC3482 Alarm Monitoring
      13. 6.3.13 LVPECL Inputs
      14. 6.3.14 LVDS Inputs
      15. 6.3.15 Unused LVDS Port Termination
      16. 6.3.16 CMOS Digital Inputs
      17. 6.3.17 Reference Operation
      18. 6.3.18 DAC Transfer Function
      19. 6.3.19 Analog Current Outputs
    4. 6.4 Device Functional Modes
      1. 6.4.1 Multi-Device Synchronization
        1. 6.4.1.1 Multi-Device Synchronization: PLL Bypassed with Dual Sync Sources Mode
        2. 6.4.1.2 Multi-Device Synchronization: PLL Enabled with Dual Sync Sources Mode
        3. 6.4.1.3 Multi-Device Operation: Single Sync Source Mode
    5. 6.5 Programming
      1. 6.5.1 Power-Up Sequence
      2. 6.5.2 Example Start-Up Routine
        1. 6.5.2.1 Device Configuration
        2. 6.5.2.2 PLL Configuration
        3. 6.5.2.3 NCO Configuration
        4. 6.5.2.4 Example Start-Up Sequence
    6. 6.6 Register Map
      1. 6.6.1 Register Descriptions
        1. 6.6.1.1  Register Name: config0 – Address: 0x00, Default: 0x049C
        2. 6.6.1.2  Register Name: config1 – Address: 0x01, Default: 0x050E
        3. 6.6.1.3  Register Name: config2 – Address: 0x02, Default: 0x7000
        4. 6.6.1.4  Register Name: config3 – Address: 0x03, Default: 0xF000
        5. 6.6.1.5  Register Name: config4 – Address: 0x04, Default: No RESET Value (WRITE TO CLEAR)
        6. 6.6.1.6  Register Name: config5 – Address: 0x05, Default: Setup and Power-Up Conditions Dependent (WRITE TO CLEAR)
        7. 6.6.1.7  Register Name: config6 – Address: 0x06, Default: No RESET Value (READ ONLY)
        8. 6.6.1.8  Register Name: config7 – Address: 0x07, Default: 0xFFFF
        9. 6.6.1.9  Register Name: config8 – Address: 0x08, Default: 0x0000 (CAUSES AUTO-SYNC)
        10. 6.6.1.10 Register Name: config9 – Address: 0x09, Default: 0x8000
        11. 6.6.1.11 Register Name: config10 – Address: 0x0A, Default: 0x0000
        12. 6.6.1.12 Register Name: config11 – Address: 0x0B, Default: 0x0000
        13. 6.6.1.13 Register Name: config12 – Address: 0x0C, Default: 0x0400
        14. 6.6.1.14 Register Name: config13 – Address: 0x0D, Default: 0x0400
        15. 6.6.1.15 Register Name: config14 – Address: 0x0E, Default: 0x0400
        16. 6.6.1.16 Register Name: config15 – Address: 0x0F, Default: 0x0400
        17. 6.6.1.17 Register Name: config16 – Address: 0x10, Default: 0x0000 (CAUSES AUTO-SYNC)
        18. 6.6.1.18 Register Name: config17 – Address: 0x11, Default: 0x0000
        19. 6.6.1.19 Register Name: config18 – Address: 0x12, Default: 0x0000 (CAUSES AUTO-SYNC)
        20. 6.6.1.20 Register Name: config19 – Address: 0x13, Default: 0x0000
        21. 6.6.1.21 Register Name: config20 – Address: 0x14, Default: 0x0000
        22. 6.6.1.22 Register Name: config21 – Address: 0x15, Default: 0x0000
        23. 6.6.1.23 Register name: config22 – Address: 0x16, Default: 0x0000
        24. 6.6.1.24 Register Name: config23 – Address: 0x17, Default: 0x0000
        25. 6.6.1.25 Register Name: config24 – Address: 0x18, Default: NA
        26. 6.6.1.26 Register Name: config25 – Address: 0x19, Default: 0x0440
        27. 6.6.1.27 Register Name: config26 – Address: 0x1A, Default: 0x0020
        28. 6.6.1.28 Register Name: config27 – Address: 0x1B, Default: 0x0000
        29. 6.6.1.29 Register Name: config28 – Address: 0x1C, Default: 0x0000
        30. 6.6.1.30 Register Name: config29 – Address: 0x1D, Default: 0x0000
        31. 6.6.1.31 Register Name: config30 – Address: 0x1E, Default: 0x1111
        32. 6.6.1.32 Register Name: config31 – Address: 0x1F, Default: 0x1140
        33. 6.6.1.33 Register Name: config32 – Address: 0x20, Default: 0x2400
        34. 6.6.1.34 Register Name: config33 – Address: 0x21, Default: 0x0000
        35. 6.6.1.35 Register Name: config34 – Address: 0x22, Default: 0x1B1B
        36. 6.6.1.36 Register Name: config35 – Address: 0x23, Default: 0xFFFF
        37. 6.6.1.37 Register Name: config36 – Address: 0x24, Default: 0x0000
        38. 6.6.1.38 Register Name: config37 – Address: 0x25, Default: 0x7A7A
        39. 6.6.1.39 Register Name: config38 – Address: 0x26, Default: 0xB6B6
        40. 6.6.1.40 Register Name: config39 – Address: 0x27, Default: 0xEAEA
        41. 6.6.1.41 Register Name: config40 – Address: 0x28, Default: 0x4545
        42. 6.6.1.42 Register Name: config41 – Address: 0x29, Default: 0x1A1A
        43. 6.6.1.43 Register Name: config42 – Address: 0x2A, Default: 0x1616
        44. 6.6.1.44 Register Name: config43 – Address: 0x2B, Default: 0xAAAA
        45. 6.6.1.45 Register Name: config44 – Address: 0x2C, Default: 0xC6C6
        46. 6.6.1.46 Register Name: config45 – Address: 0x2D, Default: 0x0004
        47. 6.6.1.47 Register Name: config46 – Address: 0x2E, Default: 0x0000
        48. 6.6.1.48 Register Name: config47 – Address: 0x2F, Default: 0x0000
        49. 6.6.1.49 Register Name: config48 – Address: 0x30, Default: 0x0000
        50. 6.6.1.50 Register Name: version– Address: 0x7F, Default: 0x540C (READ ONLY)
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 IF Based LTE Transmitter
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
          1. 7.2.1.2.1 Data Input Rate
          2. 7.2.1.2.2 Interpolation
          3. 7.2.1.2.3 LO Feedthrough and Sideband Correction
        3. 7.2.1.3 Application Curves
      2. 7.2.2 Direct Upconversion (Zero IF) LTE Transmitter
        1. 7.2.2.1 Design Requirements
        2. 7.2.2.2 Detailed Design Procedure
          1. 7.2.2.2.1 Data Input Rate
          2. 7.2.2.2.2 Interpolation
          3. 7.2.2.2.3 LO Feedthrough and Sideband Correction
        3. 7.2.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Examples
      3. 7.4.3 Assembly
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Device Nomenclature
        1. 8.1.1.1 Definition of Specifications
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information
    1. 10.1 Clarifications for DAC3482 Power Supply and Phase-Locked Loop Specification

Package Options

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

6.4.1.1 Multi-Device Synchronization: PLL Bypassed with Dual Sync Sources Mode

For single or multi-device synchronization it is important that delay differences in the data are absorbed by the device so that latency through the device remains the same. Furthermore, the outputs from each DAC are phase aligned it is necessary that data is read from the FIFO of each device simultaneously. In the DAC3482 this is accomplished by operating the multiple devices in Dual Sync Sources mode. In this mode, the additional OSTR signal is required by each DAC3482 to be synchronized.

Data into the device is input as LVDS signals from one or multiple baseband ASICs or FPGAs. Data into the multiple DAC devices can experience different delays due to variations in the digital source output paths or board level wiring. These different delays can be effectively absorbed by the DAC3482 FIFO so that all outputs are phase aligned correctly.

GUID-7B83F12C-FD57-4B04-9CFE-8CEB1F0BBFEC-low.gifFigure 6-39 Synchronization System in Dual Sync Sources Mode with PLL Bypassed

For correct operation both OSTR and DACCLK must be generated from the same clock domain. The OSTR signal is sampled by DACCLK and must satisfy the timing requirements in Section 5.9. If the clock generator does not have the ability to delay the DACCLK to meet the OSTR timing requirement, the polarity of the DACCLK outputs can be swapped with respect to the OSTR ones to create 180 degree phase delay of the DACCLK. This may help establish proper setup and hold time requirement of the OSTR signal.

Careful board layout planning must be done so the DACCLK and OSTR signals are distributed from device to device with the lowest skew possible as this will affect the synchronization process. To minimize the skew across devices, it is recommended to use the same clock distribution device to provide the DACCLK and OSTR signals to all the DAC devices in the system.

GUID-C7493064-7A11-4AE1-BF0D-D2E77B5B4E7E-low.gifFigure 6-40 Timing Diagram for LVPECL Synchronization Signals

The following steps are required to make sure the devices are fully synchronized. The procedure assumes all the DAC3482 devices have a DACCLK and OSTR signal and must be carried out on each device.

  1. Start-up the device as described in the power-up sequence. Set the DAC3482 in Dual Sync Sources mode and select OSTR as the clock divider sync source (clkdiv_sync_sel in register config32).
  2. Sync the clock divider and FIFO pointers.
  3. Verify there are no FIFO alarms either through register config5 or through the ALARM pin.
  4. Disable clock divider sync by setting clkdiv_sync_ena to β€œ0” in register config0.

After these steps all the DAC3482 outputs will be synchronized.