ASM8P18S42 Datasheet | Alliance Semiconductor Corporation

Description ASM8P18xx is a high performance, adjustable frequency, PWM controller with an integrated spread spectrum modulator for EMI reduction. It contains all the functions of a standard PWM controller along with a user configurable spread spectrum modulation with adjustable spread. ASM8P18xx allows significant system cost savings by reducing the number of PCB layers and shielding that are traditionally required to pass EMI regulation. Features 30V maximum operating voltage with CMOS technology Adjustable PWM frequencies (40 KHz to 400 KHz) Maximum Output drive current of 1A. Wide duty cycle range (0% minimum to 95% maximum) Spread spectrum modulation with adjustable spread. Under voltage lockout with hysteresis. Low startup current: 275?A maximum Pin patible with industry standard 3842 PWM controller. Temperature range - 40°C to +85°C. Thermal protection. Frequency skip mode. Available in 8-pin plastic Micro SO, P-DIP and SOIC packages. shutdown, overload and undercurrent .. ASM8P18xx is the industry’s first general purpose EMI reduction IC, specifically designed for use in SMPS systems. ASM8P18xx is patible to any other 3842 PWM controllers. ASM8P18xx is capable of driving 1A maximum current output and it covers a wide supply voltage range from 7V DC to 30V DC. The PWM frequency is selectable from 40 KHz to 400 KHz. ASM8P18xx provides under voltage lockout, thermal shutdown, overload, and undercurrent protection. It is available in 8-pin Micro SO, P-DIP and SOIC package. Applications Off-line converter DC-DC converter Monitor power supply puter/DVD/STB power supply Wireless base station power supply Tele power supply Typical Operating Circuit VDD VDD FSEL CT GND ASM8P18xx VREF RD P FB OUT ISNS R1 RC CC R2 R3 RS VIN From SMPS Output Alliance Semiconductor 2575 Augustine Drive - Santa Clara, CA - Tel: 408.855.4900 - Fax: 408.855.4999 - Notice: The information in this document is subject to change without notice. June 2005 rev 0.6 Logic Block Diagram VDD...