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LLC resonant controller enabling low standby power

UCC256303 is not recommended for new designs
Although this product continues to be in production to support previous designs, we don't recommend it for new designs. Consider one of these alternates:
open-in-new Compare alternates
Pin-for-pin with same functionality to the compared device
UCC256403 ACTIVE LLC resonant controller with ultra-low power and ultra-quiet standby operation This part offers lower audible noise in applications
Same functionality with different pin-out to the compared device
NEW UCC25660 ACTIVE Wide-VIN/VOUT 750-kHz LLC controller Capable of higher operating frequency and supports wider VIN/VOUT operation

Product details

Control mode Current Features High voltage gate driver integrated, Hybrid hysteretic control, Light load efficiency, Over Temperature Protection Vin (min) (V) 11.25 Vin (max) (V) 30 Operating temperature range (°C) -40 to 125 Topology Half bridge, LLC Rating Catalog
Control mode Current Features High voltage gate driver integrated, Hybrid hysteretic control, Light load efficiency, Over Temperature Protection Vin (min) (V) 11.25 Vin (max) (V) 30 Operating temperature range (°C) -40 to 125 Topology Half bridge, LLC Rating Catalog
SOIC (DDB) 14 59.4 mm² 9.9 x 6
  • 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
  • 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

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.

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.

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Technical documentation

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Type Title Date
* Data sheet UCC256303 LLC Resonant Controller Enabling Ultra-Low Standby Power datasheet (Rev. A) PDF | HTML 07 Jan 2019
Application note Improving Transient Response in LLC Converters Using Hybrid Hysteretic Control (Rev. B) 07 Apr 2021
Application note Migrating to UCC25640x from UCC25630x (Rev. A) 10 Dec 2019
Application brief Exceeding Modern Energy Standards with 'Always On' PFC and LLC Controllers​ (Rev. B) 01 Aug 2019
Application note Improving ZVS and efficiency in LLC converters 05 Nov 2018
EVM User's guide Using UCC25630-1EVM-291 (Rev. B) 30 Jan 2018
Application note UCC25630x Practical Design Guidelines (Rev. A) 08 Dec 2017
Application note AC Ripple Rejection in AC/DC Systems Using LLC 31 Oct 2017
Selection guide UCC25630x Selection Guide 29 Aug 2017

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

UCC25630-1EVM-291 — UCC256301 LLC evaluation module

UCC25630-1EVM-291 is an EVM of LLC resonant half-bridge DC-DC power converter with LLC controller UCC256301. UCC25630-1EVM-291 accepts DC line input from 340Vdc to 410Vdc, AC input voltage from 85 VAC to 264 VAC, and outputs nominal 12Vdc with full load output power 120W, or full output current 10A.

User guide: PDF
Not available on TI.com
Simulation model

UCC256303 SIMPLIS Model

SLUM601.ZIP (110 KB) - SIMPLIS Model
Calculation tool

SLUC634 UCC25630x Design Calculator

Supported products & hardware

Supported products & hardware

Products
LLC controllers
UCC256301 Wide vin LLC resonant controller with high-voltage start up enabling ultra-low standby power UCC256302 LLC resonant controller with high voltage start up enabling low standby power UCC256303 LLC resonant controller enabling low standby power UCC256304 Wide vin LLC resonant controller with high-voltage start up enabling low standby power
Reference designs

PMP40281 — LLC Resonant Converter Control Card Reference Design

This reference design is a a control card for LLC converter. It integrates all of the essential functions for controlling a LLC converter including the HV start-up, X-capacitor discharge and the drivers for the power FETs. By employing the advanced burst mode, it can also help the LLC converter to (...)
Test report: PDF
Schematic: PDF
Package Pins Download
SOIC (DDB) 14 View options

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