SLUSD49 September 2017 UCC256303

PRODUCTION DATA. 

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1Absolute Maximum Ratings
    2. 6.2ESD Ratings
    3. 6.3Recommended Operating Conditions
    4. 6.4Thermal Information
    5. 6.5Electrical Characteristics
    6. 6.6Switching Characteristics
    7. 6.7Typical Characteristics
  7. Detailed Description
    1. 7.1Overview
    2. 7.2Functional Block Diagram
    3. 7.3Feature Description
      1. 7.3.1 Hybrid Hysteretic Control
      2. 7.3.2 Regulated 12-V Supply
      3. 7.3.3 Feedback Chain
      4. 7.3.4 Optocoupler Feedback Signal Input and Bias
      5. 7.3.5 System External Shut Down
      6. 7.3.6 Pick Lower Block and Soft Start Multiplexer
      7. 7.3.7 Pick Higher Block and Burst Mode Multiplexer
      8. 7.3.8 VCR Comparators
      9. 7.3.9 Resonant Capacitor Voltage Sensing
      10. 7.3.10Resonant Current Sensing
      11. 7.3.11Bulk Voltage Sensing
      12. 7.3.12Output Voltage Sensing
      13. 7.3.13High Voltage Gate Driver
      14. 7.3.14Protections
        1. 7.3.14.1ZCS Region Prevention
        2. 7.3.14.2Over Current Protection (OCP)
        3. 7.3.14.3Over Output Voltage Protection (VOUTOVP)
        4. 7.3.14.4Over Input Voltage Protection (VINOVP)
        5. 7.3.14.5Under Input Voltage Protection (VINUVP)
        6. 7.3.14.6Boot UVLO
        7. 7.3.14.7RVCC UVLO
        8. 7.3.14.8Over Temperature Protection (OTP)
    4. 7.4Device Functional Modes
      1. 7.4.1Burst Mode Control
      2. 7.4.2Soft-Start and Burst-Mode Threshold
      3. 7.4.3System States and Faults State Machine
      4. 7.4.4Waveform Generator State Machine
  8. Application and Implementation
    1. 8.1Application Information
    2. 8.2Typical Application
      1. 8.2.1Design Requirements
      2. 8.2.2Detailed Design Procedure
        1. 8.2.2.1 LLC Power Stage Requirements
        2. 8.2.2.2 LLC Gain Range
        3. 8.2.2.3 Select Ln and Qe
        4. 8.2.2.4 Determine Equivalent Load Resistance
        5. 8.2.2.5 Determine Component Parameters for LLC Resonant Circuit
        6. 8.2.2.6 LLC Primary-Side Currents
        7. 8.2.2.7 LLC Secondary-Side Currents
        8. 8.2.2.8 LLC Transformer
        9. 8.2.2.9 LLC Resonant Inductor
        10. 8.2.2.10LLC Resonant Capacitor
        11. 8.2.2.11LLC Primary-Side MOSFETs
        12. 8.2.2.12Design Considerations for Adaptive Dead-Time
        13. 8.2.2.13LLC Rectifier Diodes
        14. 8.2.2.14LLC Output Capacitors
        15. 8.2.2.15BLK Pin Voltage Divider
        16. 8.2.2.16BW Pin Voltage Divider
        17. 8.2.2.17ISNS Pin Differentiator
        18. 8.2.2.18VCR Pin Capacitor Divider
        19. 8.2.2.19Burst Mode Programming
        20. 8.2.2.20Soft-Start Capacitor
      3. 8.2.3Application Curves
  9. Power Supply Recommendations
    1. 9.1VCC Pin Capacitor
    2. 9.2Boot Capacitor
    3. 9.3RVCC Pin Capacitor
  10. 10Layout
    1. 10.1Layout Guidelines
    2. 10.2Layout Example
  11. 11Device and Documentation Support
    1. 11.1Device Support
      1. 11.1.1Development Support
        1. 11.1.1.1Custom Design With WEBENCH® Tools
    2. 11.2Documentation Support (if applicable)
      1. 11.2.1Related Documentation
    3. 11.3Receiving Notification of Documentation Updates
    4. 11.4Community Resources
    5. 11.5Trademarks
    6. 11.6Electrostatic Discharge Caution
    7. 11.7Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Features

  • Hybrid Hysteretic Control (HHC)
    • Best-in-Class Transient Response
    • Easy Compensation Design
  • Optimized Low Power Features Enable 75 mW
    Standby Power Design with PFC on
    • Advanced Burst Mode
      Opto-Coupler Low Power Operation
    • Helps Enable Compliance to CoC Tier II Standard
  • Fast Exit from Burst Mode
  • Improved Capacitive Region Avoidance Scheme
  • Adaptive Dead-Time
  • Internal High-Side Gate Drivers
    (0.6-A and 1.2-A Capability)
  • Robust Soft Start with No Hard Switching
  • Over Temperature, Output Over Voltage, Input
    Over and Under Voltage Protection with
    Three Levels of Over Current Protections
  • Wide Operating Frequency Range
    (35 kHz to 1 MHz)
  • LLC Resonant Controller in SOIC16
    with High Voltage Clearance
  • External Bias Required
  • Create a Custom Design Using the UCC256303 With the WEBENCH® Power Designer

Applications

  • Digital TV SMPS
  • AC-DC Adapter
  • Gaming
  • Desktop PC

Description

The UCC256303 is a fully featured LLC controller with integrated high-voltage gate driver. It has been designed to pair with a PFC stage to provide a complete power system using a minimum of external components. The resulting power system is designed to meet the most stringent requirements for standby power without the need for a separate standby power converter, and with PFC stage running all the time. UCC256303 includes a range of features designed to make LLC converter operation well controlled and robust. This device aims to unburden the LLC designer and allow mainstream applications to benefit from efficiency advantages of the LLC topology.

UCC256303 uses hybrid hysteretic control to provide best in class line and load transient response. The control effort is approximately linearly proportional to average input current in one cycle. The control makes the open loop transfer function a first order system so that it’s very easy to compensate. The system is always stable with proper frequency compensation.

UCC256303 provides a high efficient burst mode with consistent burst power level during each burst on cycle. The burst power level is programmable and adaptively changes with input voltage, making the optimization of efficiency very easy.

Device Information(1)

PART NUMBERPACKAGEBODY SIZE (NOM)
UCC256303SOIC (14)9.9 mm x 3.9 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

UCC256303 alt_slusd49.gif

Revision History

DATEREVISIONNOTES
September 2017*Initial release.