CM6800T Datasheet | Champion Microelectronic

http://.championmicro..tw CM6800T (Turbo-Speed PFC+Green PWM) EPA/85+ PFC+PWM BO CONTROLLER Design for High Efficient Power Supply GENERAL DESCRIPTION CM6800T is a turbo-speed PFC and a Green PWM controller. It is designed to further increase power supply efficiency while using the relatively lower 380V Bulk Capacitor value. Switching to CM6800T from your existing CM6800 family boards can gain the following advanced performances: 1.) Hold Up time can be increased ~ 30% from the existing 6800 power supply 2.) Turbo Speed PFC may reduce 420 Bulk Capacitor size 3.) 420V bulk capacitor value may be reduced and PFC Boost Capacitor ripple current can be reduced 4.) No Load Consumption can be reduced 290m W at 270VAC 5.) Better Power Factor and Better THD 6.) Clean Digital PFC Brown Out 7.) PWM transformer size can be smaller 8.) Superior Surge Noise Immunity 9.) To design 12V, 5V, and 3.3V output filters can be easy 10.) The stress over the entire external power device is reduced and EMI noise maybe reduced; PFC inductor core might be reduced 11.) Monotonic Output design is easy 12.) And more… Of course, the cost can be reduced CM6800T is pin to pin patible with CM6800 family. Beside all the goodies in the CM6800, it is designed to meet the EPA/85+ regulation. With the proper design, its efficiency of power supply can easily approach 85%. To start evaluating CM6800T from the exiting CM6800, CM6800A, or ML4800 board, 6 things need to be taken care before doing the fine tune: 1.) Change RAC resistor (on pin 2, IAC) from the old value to a higher resistor value between 4.7 Mega ohm to 8 Mega ohm. Start with 6 Mega ohm for RAC first. 2.) Change RTCT pin (pin 7) from the existing value to RT=5.88K ohm and CT=1000p F to have fpfc=68Khz, fpwm=68Khz, frtct=272Khz for CM6800T 3.) Adjust all high voltage resistor around 5 mega ohm or higher. 4.) VRMS pin(pin 4) needs to be 1.14V at VIN=80VAC for universal input application from line input from 80VAC to 270VAC. 5.) At...