Infineon ICE5ASAG 60W开关电源解决方案详解

　　infineon公司的ICE5ASAG是第五代固定频率PWM控制器，采用软栅极驱动和频率抖动操作使得在轻负载和50%间有更低的EMI和更好的效率。器件工作电压（10.0~25.5 V），待机时的功耗小于10mW，内置了数字软起动，集成的误差放大器支持非隔离反激的直接反馈，主要用在家用电器，白色家电，TV，PC和服务器的辅助电源，蓝光播放器，机顶盒以及LCD/LED监视器。本文介绍了ICE5ASAG产品亮点和主要特性，框图和应用电路，以及采用ICE5ASAG和IPA80R600P7的60 W 12 V 5 V SMPS演示板DEMO_5ASAG_60W1主要特性，电路图，材料清单和PCB设计图。

　　The ICE5xSAG is the 5th generation of fixed frequency PWM controller optimized for off-line switch mode power supply in cascode configuration. The cascode configuration helps achieve fast startup. The frequency reduction with soft gate driving and frequency jitter operation offers lower EMI and better efficiency between light load and 50% load. The selectable entry and exit standby power ABM enables flexibility and ultra-low power consumption at standby mode with small and controllable output voltage ripple. The product has a wide operating range （10.0 ~ 25.5 V） of IC power supply and lower power consumption. The numerous protection functions with adjustable line over voltage protection support the power supply system in failure situations. All these make the 5th generation ICE5xSAG series an outstanding PWM controller for fixed frequency flyback converter in the market.

　　ICE5ASAG产品亮点：

　　Enhanced Active Burst Mode with selectable entry and exit standby power to reach the lowest standby power 《100 mW

　　Digital frequency reduction for better overall system efficiency

　　Fast startup achieved with cascode configuration

　　Frequency jitter and soft gate driving for low EMI

　　Integrated error amplifier

　　Comprehensive protection with input line over voltage protection

　　Pb-free lead plating， halogen-free mold compound， RoHS compliant

　　ICE5ASAG主要特性：

　　Enhanced Active Burst Mode with selectable entry and exit standby power

　　Digital frequency reduction for better overall system efficiency

　　Fast startup achieved with cascode configuration

　　DCM and CCM operation with slope compensation

　　Frequency jitter and soft gate driving for low EMI

　　Built-in digital soft start

　　Integrated error amplifier to support direct feedback in non-isolated flyback

　　Comprehensive protection with input line over voltage protection， VCC over voltage， VCC under voltage， overload/open loop， over temperature and Current Sense （CS） short to GND

　　All protections are in auto restart mode

　　Limited charging current for VCC short to GND

　　ICE5ASAG应用：

　　Auxiliary power supply for home appliances/white goods， TV， PC & server

　　Blu-ray player， set-top box & LCD/LED monitor

图1.ICE5ASAG框图

图2.ICE5ASAG和TL431与光耦在隔离反激的应用电路

图3.ICE5ASAG采用集成误差放大器的非隔离反激应用电路

　　采用ICE5ASAG和IPA80R600P7的60 W 12 V 5 V SMPS演示板DEMO_5ASAG_60W1

　　This document is an engineering report that describes a universal-input 60 W 12 V 5 V off-line isolated Flyback converter using the latest fifth-generation Infineon Fixed Frequency Controller （FFC） ICE5ASAG and CoolMOSTM IPA80R600P7， which offers high-efficiency， low standby power with selectable entry and exit standby power options， wide VCC operating range with fast start-up， robust line protection with input Over Voltage Protection （OVP） and various protection modes for a highly reliable system. This demo board is designed for users who wish to evaluate the performance of ICE5ASAG and IPA80R600P7 in terms of optimized efficiency， thermal performance and EMI.

　　This document is intended for power supply design/application engineers， students， etc. who wish to design low-cost and highly reliable systems for off-line SMPS; either auxiliary power supplies for white goods， PCs， servers and TVs， or enclosed adapters for Blu-ray players， set-top boxes， games consoles， etc.

　　This document is an engineering report for a 60 W 12 V 5 V demo board designed in an FF isolated Flyback converter topology using the fifth-generation FFC ICE5ASAG and a P7 series of HV CoolMOSTM IPA80R600P7. The demo board is operated in Discontinuous Conduction Mode （DCM） and is running at 100 kHz fixed switching frequency. The frequency reduction with soft gate driving and frequency jittering offers lower EMI and better efficiency between light load and 50% load. The selectable Active Burst Mode （ABM） power enables ultra-low power consumption. In addition， numerous adjustable protection functions have been implemented in ICE5ASAG to protect the system and customize the IC for the chosen application. In case of failures like line Over Voltage （OV）， VCC OV/Under Voltage （UV）， open control-loop or over-load， over-temperature， VCC short-to- GND and CS short-to-GND， the device enters protection mode. By means of the cycle-by-cycle Peak Current Limitation （PCL）， the dimensions of the transformer and current rating of the secondary diode can both be optimized. In this way， a cost-effective solution can easily be achieved. The target applications of ICE5ASAG are either auxiliary power supplies for white goods， PCs， servers and TVs， or enclosed adapters for Blu-ray players， set-top boxes， games consoles， etc.

图4.演示板DEMO_5ASAG_60W1外形图

演示板DEMO_5ASAG_60W1主要指标:

图5.演示板DEMO_5ASAG_60W1电路图

演示板DEMO_5ASAG_60W1材料清单:

图6.变压器结构图

图7.演示板DEMO_5ASAG_60W1 PCB设计图(1)

图8.演示板DEMO_5ASAG_60W1 PCB设计图(2)