?2010. renesas electronics corporation, all rights reserved. renesas electronics url http://www.renesas.com/pfcic 1. continuous conduction mode suitable for the system with a large amount and frequency of a current change. 2. on/off support of the main converter and the load by a pg signal and a hold function. 3. hold function against an ac temporary blackout 4. over-voltage protection with a feedback loop absence detecting function 5. quick soft-start 6. improvement of the load regulation by a gm amplifier single-function pfc control ic 380v pfc unit 100/200v gain selector hold function against ac temporary blackout over-voltage protection with feedback loop absence detecting function p.g circuit & on/off timing adjustment soft start circuit ovp 380v HA16174 pfc unit p.g circuit with on/off timing adjustment function soft start 100/200v gain selector hold function against ac temporary blackout high reliability by all required functions integrating out gnd deley pgadj pfc-on vref cao cs vcc ss eo fb iac pg ct rt dip16 or sop16 ? small radiation noise ? small peak current ? strong to current change ? relatively-simple circuit ?some complicated circuit ? large choke coil at high current area. ? large peak current ? indefinite frequency advantages weak points input voltage choke coil current input average current (1) continuous conduction (2) critical conduction in case of critical current mode, the peak current changing so large. in case of continuous current mode, peak current not so much changing. in case of lout change large current change pg signal ex.) enable to start or stop the main converter in the normal sequence by using a pg signal. ac input hold counter bulk voltage pg off voltage (adjustable) ac input bulk voltage hold counter hold timer (adjustable) the hold function achieves fast re covery since ic operation does not stop until a specified time even in case of bad power condition. ac blackout gate output (HA16174) fet out (conventional ic) fb bulk voltage feedback loop absence detecti on can stop output pulse. therefore renesas pfc ic prevents the breakings of bulk capacitor and mosfet. fb conventional ic w/o this function bulk voltage the feedback loop is down case, bulk voltage is going up abnormal voltage. then capacitor is broken. HA16174 detect the feedback loop disconnection, and stop the pulse! prevent from the breakings of bulk capacitance and power mos!! ha 16174 conv enti onal i c cut cut amp . f o r f b vr ef r2 r1 vou t ve o amp . f o r f b fb vr ef r2 r1 vou t in case of gmamp, there i s no affe cti o n of feedba ck current flow , and loa d regu latio n be comes good. conv enti onal i c ha 16174 1 . contin uous conduc ti on mode 2 . on/of f su pport for ma i n con v e r te r a n d loa d 3 . hold f unc ti on a g a i ns t a c te mpora r y bla c k out 4. o v er- v o l tag e pro t ectio n w i th a feedback loop a b sence det ecti ng functio n 6 . impro v e m ent of loa d re gula t io n by g m a m p. in f eed b ack l o o p 5. quick soft start shortens s/s time t r i a ngl e wa ve f o r m soft start po pu l a r soft start tim e re nes as c ss=4.7uf shor tened ti me= 4 .7uf x 1 v/25ua= 1 88ms. r e nesas pfc c ont rol ic f o r d i git a l-tv HA16174 fe atures small and h i g h reliabil i ty system 12 v 380 v 1.2v + rjk 501 5 h a 16 16 3 h a 16 16 7 p.g s i gnal exa m ple of ap plicatio n circuit ap r i l 2 010 ? t he h a 16174 stab ili ze s the o v e r -cu r r ent con t ro l o f p f c un it and set s the s / s inef fe ct ive t i m e by a ho ld funct i o n in t i m e of an a c te m p o r a r y b l a c kou t . ? t he h a 16163 m a ke s up a fu ll b r idge and a c h i e v es sm a ll a nd h i gh e fficienc y tra n c e s. stop th e pg sig n a l , w hen a bu l k v o ltage dro p s to le ss than setti ng v o ltag e (vth). h a 16174 s/ s: so ft s t ar t ga te ou tput output the pg si gn al at the setti ng time by a hold c o u n ter la te to stab i l i z e after the bu l k v o ltage rea c he s the prov i s ion. ov er -v o l ta g e pr otecti o n w i t h f eedback l o op abs ence detecti ng f unc ti on current t y pe of circuit suffers an affe cti on of the feedb ack current flow becau se r1, r2 impeda n c e is n o t id ea l.
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