The UCC2863x targetshigh-power, primary-side regulated flyback converters. The ability to operate in both CCM and DCMmake the device suitable for applications with a wide power range. The peak power mode allowstransient peak power delivery up to 200% of nominal rating, with only a 25% peak current increase,maximizing transformer utilization.
The transformer bias winding is used to sense output voltage for regulation, and forlow-loss input voltage sensing. Advanced sampling techniques allow CCM operation, and deliverexcellent output voltage regulation performance for opto-coupler-less designs at power levels of100 W and above.
A high-voltage current source enables fast and efficient start-up. Advanced light-loadmodes are deployed to reduce both controller and system power consumption at no load and lightload. These modes enable potential system designs to meet 30-mW no-load power for power designs upto 30 W nominal, 60 W peak.
The device has been designed for ease-of-use and incorporates many features to enable awide range of designs. Extensive protection features are included to simplify system design.
See the Device Comparison Table for details.
Feature
- High-Power, Primary-Side CV/CC Regulation
- Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM) Operation
- Built-In 700-V Start-Up Current Source
- Active X-Capacitor Discharge (UCC28630 and UCC28633)
- Adjustable Constant-Current (CC) Mode Limiting (except for UCC28630)
- High Gate Drive Current 1-A Source and 2-A Sink
- Low Power Modes for <30-mW System Standby
- Best-In-Class Light Load (10%) Efficiency >85%
- PSR design with no opto-coupler - can meet high CM isolation & surge requirements
- VDD OVP for independent indirect output OV under open-feedback fault conditions
- Peak-Power Mode for Transient Overload
- Shutdown Pin Interface for External NTC
- Protections: Overvoltage, Overcurrent, Over-Temperature, Overload Timer (UCC28630), AC Line UV, Brownout and Pin Protections
- Frequency Dither to Ease EMI Compliance (except the UCC28632)
- Create a Custom Design Using the UCC2863x With the WEBENCH Power Designer
