SLUSC82A March   2015  – March 2015 UCC24630

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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
    6. 6.6 Timing Requirements
    7. 6.7 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 Start Up and UVLO
      2. 7.3.2 Volt-Sec SR Driver On-Time Control
      3. 7.3.3 CCM Dead Time
      4. 7.3.4 Standby Operation
      5. 7.3.5 Pin Fault Protection
        1. 7.3.5.1 VPC Pin Overvoltage
        2. 7.3.5.2 VPC Pin Open
        3. 7.3.5.3 VSC Pin Open
        4. 7.3.5.4 TBLK Pin Open
        5. 7.3.5.5 VPC and VSC Short to Ground
        6. 7.3.5.6 TBLK Pin Short to Ground
    4. 7.4 Device Functional Modes
      1. 7.4.1 Start-Up
      2. 7.4.2 Normal Operation
      3. 7.4.3 Standby Operation
      4. 7.4.4 Conditions to Stop Operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 AC-to-DC Adapter, 19.5 V, 65 W
      2. 8.2.2 Design Requirements
      3. 8.2.3 Calculation of Component Values
        1. 8.2.3.1 VPC Input
        2. 8.2.3.2 VSC Input
        3. 8.2.3.3 TBLK Input
      4. 8.2.4 Application Curves
    3. 8.3 Do's and Don'ts
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 VDD Pin
      2. 10.1.2 VPC Pin
      3. 10.1.3 VSC Pin
      4. 10.1.4 GND Pin
      5. 10.1.5 TBLK Pin
      6. 10.1.6 DRV Pin
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Device Nomenclature
        1. 11.1.1.1 Definition of Terms
      2. 12.3   Electrostatic Discharge Caution
      3. 12.4   Glossary
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

1 Features

  • Secondary-Side SR Controller Optimized for 5-V to 24-V Flyback Systems
  • Operating Frequency Up to 200 kHz
  • Volt-Second Balance SR On-Time Control
  • Minimize Effect of MOSFET Device and Layout Inductance
  • CCM Operation Compatibility
  • Compatible with PSR and SSR Control
  • Auto Low-Power Detect and 110-µA Standby Mode Current
  • Wide VDD Range from 3.6 V to 28 V
  • Rail-to-Rail Gate Driver with 13-V Clamp
  • Open and Short Pin Fault Protection

2 Applications

  • 5-V to 24-V Output Flyback and Forward Converters
  • USB-PD Adapters and Chargers with Type-C Connector
  • Chargers for Smart Phones and Tablets
  • Notebook and Ultrabook Adapters
  • High Efficiency Auxiliary Power in Server, Desktop and Appliance Applications
  • Industrial and Medical SMPS

3 Description

The UCC24630 SR controller is a high-performance controller and driver for N-channel MOSFET power devices used for secondary-side synchronous rectification.

The combination of controller and MOSFET emulates a near-ideal diode rectifier. This solution not only directly reduces power dissipation of the rectifier but also reduces primary-side losses as well, due to compounding of efficiency gains.

Utilizing a volt-second balancing control method, the UCC24630 is ideal for flyback power supplies over a wide-output voltage range since the device is not connected directly to the MOSFET drain. The SR drive turn-off threshold is not dependent on the MOSFET RDS(on) which allows optimizing for maximum conduction time. Also secondary current ringing due to device and layout inductance does not affect the SR turn-off threshold.

The UCC24630 controller offers a programmable false-trigger filter, a frequency detector to automatically switch to standby mode during low power conditions and pin fault protections. The UCC24630 is compatible with DCM, TM and CCM operation.

The wide VDD operating range, wide programming range of the VPC voltage and blanking time, allows use in a variety of flyback converter designs.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
UCC24630 SOT23 (6) 2.92 mm x 1.30 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

UCC24630 alt_lusc82.gif

Gate-Drive Timing vs VDS Sensing SR Driver

UCC24630 alt2_lusc82.gif