New Industry Products

SG Releases PFC Controller Chips

April 20, 2006 by Jeff Shepard

System General (SG) today announced its new generation of power factor correction (PFC) controller chips. This brand-new product line has been developed using SG's own patented technologies to help customers simplify power system design while reducing overall operational costs. This product line is suitable for end applications requiring PFC features, such as LCD TVs, electrical ballasts for lighting, desktop computers and notebook computers. Three models have been introduced to the market, including the SG6931, SG6902 and SG6961.

Tom Yang, CEO and founder of System General states, "The old PFC solutions were quite expensive, making it difficult for customers to achieve high quality at low cost. Now, System General's patented technology has solved this problem. Our highly integrated PFC controllers will provide customers with high technical merits at an acceptable cost."

In addition to the advantage in system cost, this product line also incorporates many other technological innovations, ensuring efficiency and reliability of the power supply system. SG's patented technologies include the Multi-Vector Error Amplifier (US Patent 6,900,623) that provides dual over-current protection and the Switched Charge Multiplier-Divider (US Patent 6,812,769) that greatly improves signal noise resistance as well as an innovative divider IC that provides the PFC feature at low cost.

The new PFC controllers are available to customers as a PFC/PWM combo IC or as a standalone PFC controller IC. The SG6931 is a PFC/PWM combo-IC for forward converters, while the SG6902 is a PFC/PWM combo-IC for flyback converters. These two combo ICs integrate the PFC and PWM controllers into one single chip, and are designed to provide current transfer operations in Continuous Conduction Mode (CCM) for high output power systems rated above 150W.

Their advantages are not only a reduction in system components; they also provide several features to improve power efficiency. Apart from including main features such as Over Temperature Protection (OTP), Over Voltage Protection (OVP), Under Voltage Protection (UVP), Over Power Protection (OPP), Short Circuit Protection (SCP) and Brown-Out protection, their patented amplifier technology also improves output dynamic response. In addition, the SG6931 allows the adjustment of the maximum PWM cycle and has added a soft switching function; the SG6092 has two stages of PFC output voltage setting function and it reaches optimal power efficiency without switching under light load.

The SG6961 is a standalone PFC controller chip that has excellent power and total harmonic distortion performance, making it suitable for electrical switching operations under critical current modes. It is suited to switching power supplies rated between 70W ~ 200W, and incorporates protective circuitry such as OVP, Output Over-Current, Under Voltage Lock Out and Open Loop Protection. It also provides features such as fast dynamic response and over voltage dampening.

"The new products that we have unveiled demonstrate System General's dedication to developing power-saving technology that helps customers compete on the market. We will continue to research new and innovative technologies to provide complete power supply solutions for different fields," Yang concluded.