SNLS507C September   2016  – December 2022 DS90UB934-Q1

PRODUCTION DATA  

  1.   Features
  2. 1Applications
  3. 2Description
  4. 3Revision History
  5.   Pin Configuration and Functions
  6. 4Specifications
    1. 4.1 Absolute Maximum Ratings
    2. 4.2 ESD Ratings
    3. 4.3 Recommended Operating Conditions
    4. 4.4 Thermal Information
    5. 4.5 DC Electrical Characteristics
    6. 4.6 AC Electrical Characteristics
    7. 4.7 Recommended Timing for the Serial Control Bus
    8. 4.8 Typical Characteristics
  7. 5Detailed Description
    1. 5.1 Overview
      1. 5.1.1 Functional Description
    2. 5.2 Functional Block Diagram
    3. 5.3 Feature Description
      1. 5.3.1 Serial Frame Format
      2. 5.3.2 Line Rate Calculations for the DS90UB933/934
      3. 5.3.3 Deserializer Multiplexer Input
    4. 5.4 Device Functional Modes
      1. 5.4.1 RX MODE Pin
      2. 5.4.2 DVP Output Control
        1. 5.4.2.1 LOCK Status
      3. 5.4.3 Input Jitter Tolerance
      4. 5.4.4 Adaptive Equalizer
      5. 5.4.5 Channel Monitor Loop-Through Output Driver
        1. 5.4.5.1 Code Example for CMLOUT FPD3 RX Port 0:
      6. 5.4.6 GPIO Support
        1. 5.4.6.1 Back Channel GPIO
        2. 5.4.6.2 GPIO Pin Status
        3. 5.4.6.3 Other GPIO Pin Controls
        4. 5.4.6.4 FrameSync Operation
          1. 5.4.6.4.1 External FrameSync Control
          2. 5.4.6.4.2 Internally Generated FrameSync
            1. 5.4.6.4.2.1 Code Example for Internally Generated FrameSync
    5. 5.5 Programming
      1. 5.5.1 Serial Control Bus
        1. 5.5.1.1 I2C Target Operation
        2. 5.5.1.2 Remote Target Operation
        3. 5.5.1.3 Remote I2C Targets Data Throughput
        4. 5.5.1.4 Remote Target Addressing
        5. 5.5.1.5 Broadcast Write to Remote Target Devices
        6. 5.5.1.6 Code Example for Broadcast Write
      2. 5.5.2 Interrupt Support
        1. 5.5.2.1 Code Example to Enable Interrupts
        2. 5.5.2.2 FPD-Link III Receive Port Interrupts
        3. 5.5.2.3 Code Example to Readback Interrupts
        4. 5.5.2.4 Built-In Self Test (BIST)
          1. 5.5.2.4.1 BIST Configuration and Status
    6. 5.6 Register Maps
      1. 5.6.1 Register Description
      2. 5.6.2 Registers
      3. 5.6.3 Indirect Access Registers
      4. 5.6.4 Indirect Access Register Map
        1. 5.6.4.1 FPD3 Channel 0 Registers
        2. 5.6.4.2 FPD3 Channel 1 Registers
        3. 5.6.4.3 FPD3 RX Shared Registers
  8. 6Application and Implementation
    1. 6.1 Application Information
    2. 6.2 Power Over Coax
    3. 6.3 Typical Application
      1. 6.3.1 Design Requirements
      2. 6.3.2 Detailed Design Procedure
      3. 6.3.3 Application Curves
    4. 6.4 System Examples
    5. 6.5 Power Supply Recommendations
      1. 6.5.1 VDD Power Supply
      2. 6.5.2 Power-Up Sequencing
      3. 6.5.3 PDB Pin
      4. 6.5.4 Ground
    6. 6.6 Layout
      1. 6.6.1 Layout Guidelines
        1. 6.6.1.1 DVP Interface Guidelines
      2. 6.6.2 Layout Example
  9.   Mechanical, Packaging, and Orderable Information
  10. 7Device and Documentation Support
    1. 7.1 Documentation Support
      1. 7.1.1 Related Documentation
    2. 7.2 Glossary
    3. 7.3 Receiving Notification of Documentation Updates
    4. 7.4 Support Resources
    5. 7.5 Trademarks
  11.   Mechanical, Packaging, and Orderable Information

6.6.2 Layout Example

Stencil parameters such as aperture area ratio and the fabrication process have a significant impact on paste deposition. Inspection of the stencil prior to placement of the VQFN package is highly recommended to improve board assembly yields. If the via and aperture openings are not carefully monitored, the solder may flow unevenly through the DAP.

Figure 6-12 shows a PCB layout example derived from the layout design of the DS90UB934-Q1EVM Evaluation Board. The graphic and layout description are used to determine proper routing when designing the board. The FPD-Link III traces leading to RIN0+, RIN0−, RIN1+, RIN1− carry critical high-speed signals, and have highest priority in routing.
For STP applications, the positive and negative traces are tightly coupled with differential 100-Ω characteristic impedance.
For coaxial applications, the FPD-Link III traces must have 50-Ω characteristic impedance. As a secondary priority, loosely couple the traces with differential 100-Ω characteristic impedance.

GUID-DC3B5E9F-8DCE-4445-9B23-6325C0C06890-low.pngFigure 6-12 DS90UB934-Q1 Example PCB Layout
  1. Place vias, AC-coupling capacitors, and common-mode chokes (if used) on the FPD-Link III traces closely together so that the impedance discontinuity appears as tightly grouped as possible.
  2. If PoC is used, place a ferrite bead placed as close as possible to the FPD-Link III trace to minimize the stub seen due to the filter network.
  3. The high-speed FPD-Link III traces are routed differentially up to the connector. For the layout of a coaxial interconnects, use coupled traces with the RINx– termination near to the connector.