Infineon CoolSET ICE2QR 65 Series, Руководство по конструкции

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Quasi-resonant CoolSET design guide
ICE2QRxx65/80x
Design Guide 5 8 August 2011
1 Introduction
This design guide describes how to design quasi-resonant flyback converters using ICE2QRxx65/80x, which
is a new Quasi-resonant PWM CoolSET developed by Infineon Technologies
Firstly, the basic description of CoolSET will be given including the main features and Pin’s layout. Then an
overview of quasi-resonant flyback converter will be given, followed by the introduction of ICE2QRxx65/80x’s
functions and operations. A typical application example, input power curves, PCB layout recommendation,
product profolio and design equations will be given in the last part of this document.
2 CoolSET description
ICE2QRxxxx is a second generation quasi-resonant PWM CoolSET with power MOSFET and startup cell in a
single package optimized for off-line power supply applications such as LCD TV, and notebook adapter. The
digital frequency reduction with decreasing load enables a quasi-resonant operation till very low load. As a
result, the system average efficiency is significantly improved compared to conventional solutions. The active
burst mode operation enables ultra-low power consumption at standby mode operation and low output
voltage ripple. The numerous protection functions give a full protection of the power supply system in failure
situation. All of these make the ICE2QRxx65/80x an outstanding power CoolSET for quasi-resonant flyback
converter in the market.
In addition, numerous protection functions have been implemented in the CoolSET to protect the system and
customize the CoolSET for the chosen applications. All of these make the ICE2QRxx65/80x an outstanding
product for real quasi-resonant flyback converter in the market.
2.1
Main features

High voltage (650V/800V) avalanche rugged CoolMOS
®
with startup cell

Quasi-resonant operation

Load dependent digital frequency reduction

Active burst mode for light load operation

Built-in high voltage startup cell

Built-in digital soft-start

Cycle-by-cycle peak current limitation with built-in leading edge blanking time

Foldback Point Correction with digitalized sensing and control circuits

VCC undervoltage and overvoltage protection with Autorestart mode

Over Load /open loop Protection with Autorestart mode

Built-in Over temperature protection with Autorestart mode

Adjustable output overvoltage protection with Latch mode

Short-winding protection with Latch mode

Maximum on time limitation

Maximum switching period limitation
2.2
Pin layout
Figure 1 Pin configurations (top view), DIP-8 version; DIP-7 (Z) version; and DSO-12 (G) version;