CM6805

CM6805(A;B)/CM6806A 10-PIN Green-Mode PFC/PWM Combo CONTROLLER for High Density AC Adapter GENERAL DESCRIPTION FEATURES The CM6805A and CM6806A are the Green-Mode ‹ PFC/PWM Combo controller for High Density AC Adapter. For the power supply, its input current shaping PFC ‹ performance could be very close to the performance of the ‹ CM6800 or ML4800 leading edge modulation average ‹ current topology. ‹ CM6805A/CM6806A offers the use of smaller, lower cost bulk capacitors, reduces power line loading and stress on ‹ the switching FETs, and results in a power supply fully ‹ compliant to IEC1000-3-2 specifications. The CM6805A / ‹ CM6806A includes circuits for the implementation of a ‹ leading edge, input current shaping technique “boost” type PFC and a trailing edge, PWM. ‹ ‹ The CM6805A’s PFC and PWM operate at the same frequency, 67.5kHz. A PFC OVP comparator shuts down ‹ the PFC section in the event of a sudden decrease in load. The PFC section also includes peak current limiting for ‹ enhanced system reliability. ‹ Both PFC and PWM have the Green Mode Functions. When the load is below GMth, Green Mode Threshold, ‹ PFCOUT is turned off. The GMth can be programmed by the designer. PWM Green Mode will happen when the PWMCMP (PWM Comparator) Duty Cycle is less than ~ 6%, in the next cycle, the PWMOUT pulse will be removed ‹ until PWMCMP Duty Cycle is greater than 6%, then the next cycle, PWMOUT pulse appears. ‹ ‹ PWM has a PWMtrifault pin which can sense the ...