SUN3406 无锡日晟微电子有限公司 1.4 MHz, 600mA Synchronous Step-Down Converter GENERAL DESCRIPTION FEATURES The SUN3406 is a 1.4MHz constant frequency, slope compensated current mode PWM stepdown converter. The device integrates a main switch and a synchronous rectifier for high efficiency without an external Schottky diode. It is ideal for powering portable equipment that runs from a single cell lithium-Ion (Li+) battery. The SUN3406 can supply 600mA of load current from a 2.5V to 5.5V input voltage. The output voltage can be regulated as low as 0.6V. The SUN3406 can also run at 100% duty cycle for low dropout operation, extending battery life in portable system. Pulse Skipping Mode operation at light loads provides very low output ripple voltage for noise sensitive applications. • • • • The SUN3406 is offered in a low profile (1mm) 5-pin, SOT package, and is available in an adjustable version and fixed output voltage of 1.2V, 1.5V and 1.8V. • • • • • • • • • • High Efficiency: Up to 96% 1.4MHz Constant Switching Frequency 600mA Output Current at VIN=3V Integrated Main switch and synchronous rectifier. No Schottky Diode Required 2.5V to 5.5V Input Voltage Range Output Voltage as Low as 0.6V 100% Duty Cycle in Dropout Low Quiescent Current: 250µA Slope Compensated Current Mode Control for Excellent Line and Load Transient Response Short Circuit Protection Thermal Fault Protection <1µA Shutdown Current Space Saving 5-Pin SOT23 package Output voltage adjustable （输出电压可调） APPLICATIONS EVALUATION BOARD • • • • • • • Standard Demo Board SUN3406ET5-02 Cellular and Smart Phones Microprocessors and DSP Core Supplies Wireless and DSL Modems PDAs MP3 Player Digital Still and Video Cameras Portable Instruments Dimensions (mm) 60X x 60Y x 1.6Z Efficiency vs Output Current Typical Application 100 90 VIN = 2.7V EFFICIENCY (%) 80 VIN = 3.6V 70 60 50 40 VIN = 4.2V 30 Figure 1. Basic Application Circuit with SUN3406 adjustable version, Vout = 1.8V www.sunriseic.net 20 10 0.1 VOUT = 1.8V TA = 25C 1 10 100 OUTPUT CURRENT (mA) 1000 [email protected] 无锡日晟微电子有限公司 SUN3406 无锡日晟微电子有限公司 Ｗｕｘｉ Ｓｕｎｒｉｓｅ Ｍｉｃｒｏｅｌｅｃｔｒｏｎｉｃｓ Ｃｏ．，Ｌｔｄ 无锡地址： 江苏省无锡市蠡园经济开发区标准厂房Ａ４栋３０８ 电话：０５１０－８５１６７３９１ 传真：０５１０－８５１６７３９１ 网址：ｗｗｗ．ｓｕｎｒｉｓｅｉｃ．ｎｅｔ 深圳地址： 广东省深圳市福田区彩田路福源大厦１栋２２Ｆ 电话：１８８２０２４９８０３（电信座机） 电话：１８８１８７８５７２１（电信座机） 传真：０７５５－８２９０２１８３ 网址：ｗｗｗ．ｓｕｎｒｉｓｅｉｃ．ｎｅｔ 邮箱：ｓａｌｅｓ＠ｓｕｎｒｉｓｅｉｃ．ｎｅｔ www.sunriseic.net [email protected]