LD7793BTransition-Mode PFC and Quasi-Resonant / Frequency Modulation Current Mode PWM Controller
The LD7793B/I/O features transition mode Power Factor Correction (PFC) voltage mode controller and Hybrid Quasi-Resonant (QR) / Pulse Frequency Modulation (PFM) current mode PWM controller for high power application.
There are adjustable PFC on/off, zero current detection (ZCD) and flyback QR/PFM operating mode selection with frequency swapping mechanism to achieve better performance.
The IC also integrates several functions of protection, such as Brown-in/out Protection (BNI/BNO), Over Load Protection (OLP), Over Temperature Protection (OTP), PFC Bulk Over Voltage Protection (PFCOVP), PFC Under Voltage Protection (PFCUVP), Output Over Voltage Protection (FBAUXOVP), Over Current Protection (OCP) with high / low line compensation and a protection pin PROT for customize control. Therefore it can protect the system from damage due to occasional failure.
The LD7793B/I/O is available in a SOP-16 package.
Features
- Integrated Boost PFC and QR/PFM Flyback controller
- Voltage mode transition operation on PFC
- Current mode QR/PFM operation on Flyback
- Frequency swapping operation on Flyback
- Brown in/out protection and X-cap discharge function
- Internal soft-start function and PFC on/off control
- OVP (Over voltage protection)
- OCP (Cycle-by-cycle current limiting)
- Internal OTP function and external protection pin
- 500/-1000mA PFC gate source/sink capability
- 700/-1000mA Flyback gate source/sink capability
Applications
- AC-DC power adapter
- Open frame SMPS
