Low Cost PC Power/Clone PC market Replace Passive PFC with Active PFC Single Range (230Vac only) Power (70% market)

Transcription

1 CM6805A/B Low Cost PC Power/Clone PC market Replace Passive PFC with Active PFC Single Range (230Vac only) Power (70% market) Passive to Active PFC cm6805a/b PFC Single Switch Forward,Dual Switch Forward or Fly-back fixed switching frequency (67.5Khz or 100Khz) CM6805A/B: 10 pin SOIC fpfc = fpwm = 67.5Khz(05A) or 100Khz(05B)

2 CM6805 family could drive BOM 20% lower than 6800A $ 10 pin SOIC PFC/PWM combo allows Less external components (about 14 components less) $ Leading Edge PFC/Trailing Edge PWM 450V Bulk Cap can be reduced $ Digitized PWM maximum duty, 50% 450V Bulk Cap can be further reduced $ CM6805 specialized feature with Powder Iron PFC core(230v AC) $ Single Range Power reduces PFC Mosfet $ Passive PFC has the higher cost in shipping PFC tri-fault and PWM tri-fault UL1950 (Passive PFC cannot meet it) No load consumption spec. cannot be met by Passive PFC; Easy for CM6805 family Smooth On/Off which single PFC with single PWM is difficult $ As results, the BOM cost is lower than Passive PFC

3 L N $1.5 L12 L11 PWM Stage 680uF/200V C1 680uF/200V C2 $0.8 9N9 0 $0.16 UC3842 Copper cost cost up Universal 300W Cost~$2.46>>>>>$2.XX

4 PWM Stage T Iron Powder ER VDC $0.6 $ N60 $0.7 $ uF/450V 9N90 $0.5 CM6805A/B Replace Passive plan gain 5% cost down Universal 300W Cost~$2.72>>>>2.584>>>>2.456>>>>2.XX(shipping cost) Production gain 5% cost down

5 2 3 CM6800 VS CM6805A/B part count GBL408 IN EMI Circuit L FG N IN W(s) 0.2 2W(s) 1uF/400V AC INLET GND 380VDC 1M 1% VCC 22uF/25V 0.1uf/25v M1% 0.047UF 1M 1M 1N A/600V B 1M 1% 0.47uF/16V 430K 1% 0.047uF VCC ISENSE 16 VEAO 2 IAC CM VFB Vrms 0.5M 1% 30.1K 0.47uF/25V 243K 36.5K 0.47uF/25V 1N N60 10K 150uF/420V 4700pF 22K 6 12 VDC PFC OUT 1 IEAO 11 PWM OUT PWM OUT R16 10 B E C 470pF 13K 1% 1000pF 2.49K 1% 2K 1% ISO1A 817C 470pF VREF 13K 1% 0.1uF 14 8 VREF RAMP2 7 9 RAMP1 DCIlim GND SS pF 2200pF 0.1uF PF PWM IS 470pF/250V 380VDC 1M R3 47 R4 15V C P 2 CM6805A GND PWM OUT IAC PFC OUT 10 9 PWM DR PFC DR 3 Isense VCC 8 VCC VCC 4 VEAO PWM TriF 7 5 VFB VI 6 R7 56K R5 1K External Component up to $:0.04 savings Ic Cost up to 15%~20% savings $:0.1 R11 10K 1N4148 1N4148 C2 104P C6 474P R8 330K C7 473P C8 103P R10 13K C4 102P C LTV817 B 3 R6 330 PWM IS

6 Champion PFCPWM combo IC benefit Bulk Cap. up to savings $:0.2

7 Digitized PWM maximum duty, 50% 450V Bulk Cap can be further reduced T ER VDC Bulk cap 12V Vout 14N50 180uF/450V Hold up time PG Δ7.8ms V tolerance -20%~tolerance (X) M tolerance 10%~20%(M) M tolerance (V) Bulk cap up to $:0.05(7%) savings Hold up time can gain 6ms

8 Choke 材質 Powder 注意 H 的變化 (B) Ferrite-Core 注意 B 的變化 ( 一般 Ferrite s le>poder s le)

9 Powder 一般工作區域 >Ferrite Powder s Permeability 愈高 --- DC-Bias 愈差

10 Powder s Permeability 愈高 --- B 愈高 ( 相同的 H) PL(core-loss)

11 2 3 Application circuit E.M.I GBU L FG IN5406 N IN W 0.47uF/400V AC INLET 1N5406 ER VDC T VDC 1M R3 47 R4 15V C P 2 CM6805A GND PWM OUT IAC PFC OUT 10 9 PWM DR R /2W(S) 10 14N50 180uF/450V VCC 3 4 Isense VEAO VCC PWM TriF 8 7 R7 R5 1K VCC K 5 6 VFB VI 56K 470pF/250V R11 10K 1N4148 R8 330K R10 13K C4 102P 4 LTV817 B 3 C2 104P C6 474P C7 473P C8 103P R6 330 PWM IS 1N4148 C V 12V PF 10.2K 1% ISO1A 817C 380VDC B 20/100V 1K 12V 1uF/450V PF 2200uF/16V 2200uF/16V 4.7K 0.1uF IA/1000V GND 39.2K 1% 2200PF 30/60V 5V PWM OUT 1N N PF uF/10V 2200uF/6.3V 4.75K 1% 1/8W TL431 1K GND PWM IS 0.2/2W(S)

12 Goal:P.F&V380 Control 1 x e 0 plant controller Y Control 2 boost converter vg Vout vin C380 i g i in v in Rsense θ t e (s) G I i g α V g V380????

13 PFC&regulation boost converter vg Vout vin C380 i g Rsense K vctrl v g α i g e (s) G I K vctrl G V (s) Vref

14 PFC&regulation boost converter vg Vout vin C380 i g IAC Isense Rsense e Ieao G I (s) Vrms v 2 g 2Re = V R L A 2 A = v g v 2 g 2ARe = V R L A K vctrl Veao G V (s) VFB Vref

15 PFC(Leading-edge) Waveform discuss Ramp1 VIeao PFC Ramp1 VIeao Veao PFC

16 Waveform discuss Ramp2 PWM(trailing-edge) VDC PWM Ramp2 VDC PWM

17 CM6805A/B/CM6903 PFC Controller: Leading Edge Modulation with Input Current Shaping Technique (I.C.S.T)

18 Boost-converter L D L D L D v g i g S C RL Vo v g i g S C RL Vo v g i g S C RL Vo S Re R = e v g i g θ i in v in t i L ON v g ( t ) L OFF Vo vg ( t ) L < i g >=< il v g > < il > Vout < id > V L ( t ) V D i D v g V o v ( t) g V o Vo vg ( t ) L t < i < d (1 d) >= V 2 out i d >= Re V t T off out sw R e V out V g = 1 (1 d) D T s (1-D) T s T 0 s

19 boost converter vg Vout vin C380 i g ON OFF ON OFF Rsense vctrl G V (s) Vref

20 . v g (t ) sw sw-off sw-on Rsense IAC VCC 7 VFB 4.5K 400K C 45 ISENSE 100K ISENSE AMP.. SUM PFCCMP -. VFB V. VEAO CM6805A/B

21 Rac filter(pin2) Rac 作為 slope compensation 斜率補償用 調整作為 THD enhance Rac 以 IC 內部阻值作為選擇依據 Iac impedance Rac Part.No. 5k 1~2M CM6805/06

22 Isense(Pin3) compensation(cm6800 同 ) Isense 之訊號需 filter 為 1/6~1/10 switching frequency 1 Isense frequency = = 2π R C is is 1 6 ~ 1 10 f s Ris 選用 47Ω = = ~ fs = π 47 C 6 10 is C = n~50.9nf is 可選用 0.1µ F

23 PFC Soft Star PWM CLK 10 ms Soft Start CM6805A/B V C C VEAO Bulk Cap PWM duty

24 Veao(pin4) compensation(cm6800 同 ) VEAO 的補償為乘上 zero-pole network, 一般選擇其 unitygain(crossover-frequency) 為 0.5 line-frequency=25hz or 30Hz, zero 的位置為 0.1pole

25 VFB Pin(5) 1 2π R fb C fb > 150Hz PFCVout Ex 1 : > Hz 2π 47k C 150 fb VFB C fb < 22nF 47k C fb C 可選用 102或 103 fb

26 PWM Stage VCC Rp 9N90 PWM CMP VI 1.5V V1 CVI RVI V2 Rsense VCC VCE (V I) Rp = = = 1.25K photo couple curret 10mA

27 ON OFF traditional current mode full load light load N S ratio(x ) light load N VI mode ratio(v ) S full load

28 VI (Pin6) R V I = V V 1.5( V I ) RsensePeak photo Couple Current(Full Load) = 1.5 VRsensePeak Photo Couple Current(Full Load) 一般約取 V RsensePeak 為 1. 25V = 0.25 Photo Couple Current(Full Load)0.5mΑ 協助提升系統的暫態響應能力, 一般而言, 設計目標是讓控制迴路和 45 度相位邊限 (phase margin), CVI 與 Rsense 極點控制濾波在開關頻率內 1 1 CV I = = 4700PF 2π R fsw 2π K V I

29 VI (Pin6) Bulk Cap Bulk Cap VI V o l t a g e m o d e VI PWM soft start duty PWM out PWM out VI PWM out

30 V e a o PFC PWM timing Bulk cap Bulk cap Veao PWM PFC PWM PFC

31 100Vac, Pin=75W PF= Vac, Pin=75W PF= Vac, FullLoad PF= Vac, Full Load PF=0.985

32 Improve and Enhance THD 1M 47K 1 GND CM6805A PWM OUT V 0.1uF PF IAC Isense PFC OUT VCC VEAO PWM TriF VFB VI

33 Disable PWM skipping 1 GND CM6805A PWM OUT 10 2 IAC PFC OUT 9 3 Isense VCC 8 4 VEAO PWM TriF VFB VI 0 68K PWM OUT MOS 4700PF 510 PWM Rsense