Click to expand full text
DATA SHEET www.onsemi.com
Advanced Secondary Side LLC Resonant Converter Controller with Synchronous Rectifier Control
FAN7688
SOP16 CASE 565BF
MARKING DIAGRAM
Description The FAN7688 is an advanced Pulse Frequency Modulated (PFM)
controller for LLC resonant converters with Synchronous Rectification (SR) that offers best in class efficiency for isolated DC/DC converters. It employs a current mode control technique based on a charge control, where the triangular waveform from the oscillator is combined with the integrated switch current information to determine the switching frequency. This provides a better control−to−output transfer function of the power stage simplifying the feedback loop design while allowing true input power limit capability.