The UCC29950 provides all the control functionality for an AC-to-DC converter with a CCM boost Power Factor Correction (PFC) stage followed by an LLC converter stage. The controller is optimized to allow ease of use.
●Proprietary CCM PFC algorithms enable the system to achieve high efficiency, smaller converter size with high power factor. The integrated LLC controller enables a high-efficiency DC-to-DC conversion stage utilizing soft switching for low EMI noise. Integration of PFC control and LLC control in a combo controller allows the control algorithms to take advantage of information from both stages.
●The controller includes a control circuit for start-up using a Depletion Mode MOSFET with internal device power management that minimizes external component requirements and helps lower system implementation costs.
●To further reduce the standby power an X-Cap discharge circuit is integrated. The UCC29950 implements a complete suite of system protection functions, including AC line brownout, PFC bus under voltage PFC and LLC, over current and thermal shutdown.
● High Efficiency PFC and Half-Bridge Resonant LLC Combo Controller
● Continuous Conduction Mode (CCM) Boost Power Factor Correction
● Supports Self-Bias or Auxiliary (external) Bias Mode of Operation
● PFC Loops Fully Internally Compensated
● PFC Stage Design in 3 Easy Steps
●(design voltage feedback, current feedback and power stage)
● Fixed 100-kHz PFC Frequency with Dithering for Ease of EMI Compliance
● True Input Power Limit, Independent of Line Voltage
● Fixed LLC Frequency Operating Range of 70 kHz to 350 kHz
● Dead-Time Varied Across Load Range for LLC Half-Bridge Power Stage to Extend ZVS Range
● Three-Level LLC Over-Current Protection
● Hiccup Mode Operation for Continuous Overload and Short-Circuit Power Protection
● Low Standby Power Consumption Enabled by Active Control of High-Voltage Start-Up MOSFET and X-Cap Discharge Function
● Built In Soft-Start and Converter Sequencing to Simplify Design
● AC Line Brownout Protection, with Fail Indicator
● PFC Bus Over-Voltage and Under-Voltage Protection
● Over-Temperature Protection
● External Gate Drivers for Scalability with Power Level
● SOIC-16 Package
