Fairchild Semiconductor’s FAN7621 resonant controller, suitable for LCD and PDP TVs, servers, game consoles and LED lighting applications, simplifies design, reduces bill of materials and provides advanced protection functions. It integrates a high-side gate-drive circuit, a current-controlled oscillator, frequency- limit circuit, soft start and numerous protection functions in a 16-pin SOP/DIP package—eliminating the need for expensive external circuitry such as pulse transformers. The FAN7621’s internal high side gate-drive circuit offers common-mode noise cancellation, ensuring excellent noise immunity, enabling the application to meet stringent EMI specifications.
The FAN7621 offers designers a zero voltage switching (ZVS) technique that reduces switching noise, allows the use of a smaller and less expensive EMI filters, and reduces switching losses in MOSFETs and rectifiers. Compared to conventional hard-switching converter topologies, efficiency is improved by 10 percent and for applications such as PDP-TVs, efficiency reaches 97 percent. An added advantage of this ZVS technique is the dramatic reduction in switching noise up to about 5dB compared to hard-switching techniques.
Fairchild Semiconductor
www.fairchildsemi.com
