ICE2QS02G

准谐振PWM控制器 Quasi-Resonant PWM Controller

Description

is a second generation quasi-resonant PWM controller optimized for off-line power supply applications such as LCD TV, audio and printers, where an auxiliary power supply for the IC is provided. The digital frequency reduction with decreasing load enables a quasi-resonant operation till very low load. As a result, the system efficiency is significantly improved compared

to a free running quasi resonant converter implemented with maximum switching frequency limitation only. In addition, numerous protection functions have been implemented in the IC to protect the system and customize the IC for the chosen application. All of these make the ICE2QS02G an outstanding product for real quasi-resonant flyback converter in the market.

Features

• Quasi-resonant operation

• Load dependent digital frequency reduction

• Built-in digital soft-start

• Cycle-by-cycle peak currentlimitation with built-in leading edge blanking time

• VCC undervoltage protection

• Mains undervoltage protection with adjustable hysteresis

• Foldback Point Correction with digitalized sensing and control circuits

• Over Load Protection with adjustable blanking time

• Adjustable restart time after Over Load Protection

• Adjustable output overvoltage protection with Latch mode

• Short-winding protection with Latch mode

• Maximum on time limitation

• Maximum switching period limitation