LD7552

www.DataSheet4U.com LD7552 2/21/2005 Green-Mode PWM Controller General Description The LD7552 is a low cost, low startup current, current mode PWM controller with green-mode power-saving operation. The integrated functions such as the leading-edge blanking of the current sensing, internal slope compensation and the small package provide the users a high efficiency, minimum external component counts, and low cost solution for AC/DC power applications. The special green-mode control does not only achieve low power consumption but also offer a non-audible-noise operation when the LD7552 operates under light load or no load condition. The LD7552 is designed for the switching adaptor with 30W~60W output. The LD7552 is offered in both SOP-8 and DIP-8 package. Patent pending z z z z z z z z z Features z High-Voltage CMOS Process with Excellent ESD Protection Very Low Startup Current (Typical 5µA) Under Voltage Lockout (UVLO) Current Mode Control with Cycle-by-Cycle Peak Current Limiting Leading-Edge Blanking on CS Pin Programmable Switching Frequency Internal Slope Compensation Non-audible-noise Green Mode Control 500mA Driving Capability Proprietary Green-Mode Control for Power Saving 1 Applications z z z Switching AC/DC Adaptor and Battery Charger Open Frame Switching Power Supply 384X Replacement 1 Note: Please see Application Information Typical Application AC input EMI Filter VCC 40V 16.0V/ 11.4V UVLO OUT RT COMP LD7552 OSC Control Logic photocoupler Divider CS...