Allegromicro STR-X6757离线准谐振SMPS解决方案

Allegromicro 公司的STR-X6757是离线准谐振开关稳压器,具有比通常的PWM解决方案更低的EMI噪音特性,特别是频率大于2MHz时. STR-X6757采用TO-3P封装,包含控制器芯片(MIC)和650 VDSS/0.62Ω RDS(on)的MOSFET,230VAC输入时输出功率高达320W,通用电压输入达到165W,主要用于STB, LCD PC监视器,LCD TV,打印机和扫描仪.本文介绍STR-X6757主要特性和优势, 方框图和典型应用电路.

STR-X6757: Off-Line Quasi-Resonant Switching Regulators

The STR-X6757 is a quasi-resonant topology IC designed for SMPS applications. It shows lower EMI noise characteristics than conventional PWM solutions, especially at greater than 2 MHz. It also provides a soft-switching mode to turn on the internal MOSFET at close to zero voltage (VDS bottom point) by use of the resonant characteristic of primary inductance and a resonant capacitor.

The package is a fully molded TO-3P, which contains the controller chip (MIC) and MOSFET, enabling output power up to 320 W at 230 VAC and 165 W at universal input. The bottom-skip mode skips the first bottom of VDS and turns on the MOSFET at the second bottom point, to minimize an increase of operating frequency at light output load, improving systemlevel efficiency over the entire load range.
..

查看全文