• Hybrid Hysteretic Control (HHC)

• Best-in-Class Transient Response

• Easy CompensationDesign

• Optimized Low Power Enable 75 mWStandby Power Design with PFC on

• Advanced Burst ModeOpto-Coupler Low Power Operation

• Helps Enable Compliance to CoC Tier IIStandard

• Fast Exit from BurstMode

• 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 HardSwitching

• 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)

• Nemko Certification for X CapDischarge Function

• Wide DC Input Range

• Enables Wide AC Input Range

• PFC StartupNot Required For LLC Startup

• Create a Custom Design Using the UCC256304 With theWEBENCH? Power Designer

All trademarks are the property of their respective owners.

The UCC256304 is a fully featured LLC controller with integrated high-voltage gatedriver. It has been designed to pair with a PFC stage to provide a complete power system using aminimum of external components. The resulting power system is designed to meet the most stringentrequirements for standby power without the need for a separate standby power converter.UCC256304uses hybrid hysteretic control to provide best in class line and load transient response. Thecontrol makes the open loop transfer function a first order system so that it’s very easy tocompensate and is always stable with proper frequency compensation.

The UCC256304 is unique in that the controller is able to operate over a large DC inputrange. This is accomplished by making the input overvoltage sense threshold much larger than theinput voltage start threshold. This allows the LLC to startup and enter a low power standby modewithout the need to enable the PFC and enables the LLC to accommodate an extensive range of commonAC inputs.

UCC256304 provides a highly efficient burst mode with consistent burst power level duringeach burst on cycle. The burst power level is programmable and adaptively changes with inputvoltage.