(14) PCB Layout Considerations attention, SG6931 has two ground pins. Wiring should follow some good experience in high-frequency, or RF, to avoid long board traces and components lead. Decoupling capacitors should be distributed in the SG6931 next. Proposed OPFC feet and OPWM feet and gate MOSFET in series between a 5 to 20 were European resistor. the PFC and PWM-level interference between the isolated levels is also very important. Figure 10 is the circuit board layout example. which ground a foot from the SG6931's GND connected to the decoupling capacitor, its impedance should be as low as possible, its alignment should be as short as possible. ground 2 to provide signal grounding, decoupling capacitor should be directly related to CDD, and / or the SG6931's GND pin connection. ground three independent from the decoupling capacitor connected to the PFC output capacitor CO. Among them, the output capacitor CO of the land is the main power switch ground reference. In order to provide a good ground reference level to reduce PFC and PWM switching noise, ground wiring 6 and 7 should be as close as possible, the resistance should be very low. IPFC feet through R3 connected directly to the RS pin,网络布线, to improve the noise resistance (if not careful, it could be connected with the ground 2 and error). IMP feet and legs should ISENSE with resistor R2 and the RP, and the other endpoint RS direct connection.