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march 2017 ? 20 15 semiconductor components industries, llc. www.on semi.com FAN6204A ? rev. 1. 1 FAN6204A mwsaver ? syn chronous rectification controller for flyback and forward freewheeling rectification fan 6204a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification features ? mwsaver ? technology: - internal green m ode to stop sr switching for lower no - load power consumption - 1.1 ma ultra - l ow green mode operating current ? sr c ontroller ? suited for flyback c onverter in qr, dcm , and ccm o peration ? suited for forward f reewheeling r ectification ? pwm f requenc y t racking with secondary - s ide w inding v oltage d etection ? ultra - l ow v dd o perating v oltage for v arious o utput v oltage a pplication s ( 5 v~ 24 v) ? v dd p in o ver - v oltage p rotection (ovp) ? 12 v ( typical ) gate d river c lamp ? 8 - p in sop p ackage applications ? ac/dc nb adapters ? open - frame smps ? battery charger description fan 6204a is a secondary - side synchronous rectification (sr) contro ller to drive sr mosfet for improving efficiency . the ic is suitable for f lyback converter s and f orward f ree - wheeling rectification . FAN6204A can be appl ied i n continuous or discontinuous conduction mode (ccm and dcm) and quasi - resonant (qr) f lyback conver ter s based on t he proprietary innovative linear - p redict timing - control technique . the benefits of this technique include a simpl e control method without current - sense circuitry to accomplish noise immunity . w ith pwm frequency tracking and secondary - side wi nding voltage detection , FAN6204A can operate in both fixed - and variable - frequency systems. in green mode, the sr controller stop s all sr switching operation to reduce the operating current. p ower consumption is maintain ed at minimum level in light - load condition. ordering information part number operating temperature range package packing method fan 6204amx - 40 c to + 1 0 5 c 8 - p in , small outline package (sop) tape & reel
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 2 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification application diagram s figure 1. typical application circuit for flyback converter figure 2. typical application circuit for forward freewheeling rectification internal block diagram figure 3. functional b lock d iagram v i n q 1 v d d r e s a g n d g n d l p c f a n 6 2 0 4 a r 1 r 2 r 3 g a t e 8 3 5 7 6 4 q 2 r 4 i s r v d e t v l p c v r e s v o u t v d d r e s a g n d g n d l p c v o u t v i n f a n 6 2 0 4 a r 1 r 2 r 3 q 1 g a t e 8 3 5 7 6 4 q 2 r 4 q 2 5 + - 4 . 8 v / 4 . 5 v i n t e r n a l b i a s 5 a / v v c t v d d 8 l p c e n a b l e 1 a / v s r q q 3 4 c t i c h r i d i s c h r g n d g a t e d r i v e p w m b l o c k 2 7 . 5 v / 2 5 . 4 v o v p 5 0 k 9 5 0 k v l p c - e n 0 . 0 5 v d d g r e e n m o d e t d i s f r e q u e n c y t r a c k i n g d e t e c t o r t s r - m a x r i s i n g e d g e c a u s a l f u n c t i o n r e s e t 0 . 0 5 v d d 2 a g n d 1 6 a g n d a g n d 7 r e s c a l c u l a t e v l p c - e n 2 v + - + - + - 1 s b l a n k i n g r e s e t
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 3 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification marking information figure 4. marking d iagram pin configuration figure 5. pin assignments pin definitions pin # name description 1 agnd signal ground . 2 agnd signal ground . 3 gate driver output. the totem - pole output driver for driving the power mosfet. 4 gnd ground . mosfet s ource c onnection. 5 vdd power supply . t he threshold voltages for start up and turn - off are 4.8 v and 4.5 v , respectively. 6 agnd signal ground . 7 res reset control of l inear p redict. the res pin is used to detect the output voltage level thr ough a voltage divider . an internal current source, i dischr , is modulated by th e voltage level on the res pin. 8 lpc winding d etection. this pin is used to detect the voltage on the winding during the on - time period of the primary gate. : l o go z: plant code x: year code y: week code tt: die run code t : package t ype (n = dip, m = sop ) m : manufa cturing flow c ode z x y t t 6 2 0 4 a t m l p c a g n d v d d r e s a g n d g a t e a g n d g n d 1 2 3 4 5 6 7 8
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 4 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification absolu te maximum ratings stresses exceeding the absolute maximum ratings may damage the device. the device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. in addition, extende d exposure to stresses above the recommended operating conditions may affect device reliability. the absolute maximum ratings are stress ratings only. symbol parameter min. max. unit v dd dc supply voltage 30 v v l lpc, r es - 0.3 7 .0 v p d power dissipati on (t a =25 c ) 0.8 w ja thermal resistance (junction - to - air) 151 c /w jc thermal resistance (junction - to - case) 58 c /w t stg storage temperature range - 55 + 150 c t j junction temperature - 40 + 150 oc t l lead temperature (soldering 10 seconds) + 260 c esd human body model 5 kv charged device model 2 notes: 1. stresses beyond those listed under a bsolute m aximum r atings may cause permanent damage to the device. 2. all voltage values, except differential voltages, are given with respect to gnd pin .
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 5 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification electrical characteristics v dd = 1 5 v and t a = 25c unless otherwise noted. symbol parameter conditions min. typ. max. unit v op continuously operating voltage v dd - off 28.5 v v dd - on turn - on threshold voltage 4.3 4.8 5.3 v v dd - off turn - off threshold volta ge 4 .0 4.5 5 .0 v v dd - hyst v dd - on C v dd - off 0.1 0.3 0.5 v i dd - op operating current v dd =15 v, l pc = 5 0 k hz , mosfet c iss =6 000 pf 7 8 ma i dd - green operating current in green mode v dd =15 v 1 .1 1. 3 ma i dd - st start up current v dd < v dd - on 150 200 ? a v dd - ovp v dd over - voltage protection 26 .0 27.5 28.5 v v dd - ovp - hyst hysteresis v oltage for v dd ovp 1.8 2.1 2.4 v t vdd - ovp v dd ovp debounce time 40 70 100 ? s output driver section v z gate output clamp voltage 10 12 14 v v ol output v oltage low v dd =6 v, i o =50 ma 0.5 v v oh output v oltage high v dd =6 v, i o =50 ma 4 v t r rising time v dd =12 v, c l =6 nf, out=2 v~9 v 30 70 120 ns v dd =6 v, c l =6 nf, out=0.4 v~4 v 70 120 170 ns t f falling time v dd =12 v, c l =6 nf, out=9 v~2 v 20 50 100 ns v dd =6 v, c l =6 nf, out=4 v~0 .4 v 20 90 130 ns t pd_high_lpc propagation delay to turn - on gate (lpc t rigger) t r : 0 v~2 v, v dd = 12 v 250 ns t pd_low_lpc propagation delay to turn - off gate (lpc t rigger) ( 3 ) t f : 100%~90%, v dd = 12 v 180 ns t m ax - period limitation between lpc r ising e dge to gate f alling e dge 22.5 25.0 28 .0 ? s v pmos - on internal pmos t urn - o n to p ull - high g ate ( 3 ) 8.3 v v pmos - on - hys hysteresis v oltage o n ( 3 ) 0.9 v t inhibit gate i nhibit time m 2 o ption ( e nable ) 1. 6 2 .2 2.8 ? s v gate - pull - high gate pull - high voltage v dd = 5 v 4.5 v lpc s ection t bnk blanking time for charging c t 400 500 600 ns t delay - comp sampling c ontinuous t ime for t bnk c ompensation ( 3 ) 1 ? s v lpc - source lpc lower clamp voltage s ource i lpc = 5 a 0.1 0. 2 0. 3 v i lpc - source lpc source c urrent v lpc = 0 v 40 8 0 120 ? a v lpc - en t hreshold v oltage to e nabled sr switching v lpc - en = v lpc - hig h x 0.8 3 at v lpc - high x 0.83 < 2 v , v o =15 v, v o =v dd , v lpc - high = 1.2 v 0.85 1 .00 1.15 v v en - clamp t hreshold c lamp v oltage to e nable sr switching v lpc - en =2 v at v lpc - high x 0.83 > 2 v 2 v v lpc - th - high threshold v oltage on lpc r ising e dge decrease vlpc from 0.05 v o +0. 05 , v o =15 v , v o =v dd 0.7 0.8 0.9 v t b nk - dis blanking t ime at the falling edge of v lpc prevent lpc s pike to t urn - o ff g ate 350 ns
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 6 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification electrical characteristics v dd = 1 5 v and t a = 25c unless otherwise noted. symbol parameter conditions min. typ. max. unit lpc section (continued) v lpc - clamp - h higher clamp v oltage ( 3 ) 6 v v lpc - dis lpc v oltage to d isable sr g ate 4 .0 4.2 4.4 v t lpc - high debounce t ime for d isable sr g ate 1 ? s res s ection v res - en t hreshold v oltage of v res to e nable sr mos fet 0.6 0 0.75 0.9 0 v t res - low d ebounce t ime to d isable res f unction 1 2 s v res - cla mp - h higher clamp v oltage ( 3 ) 6 v k res - drop res d ropping p rotection r atio within o ne c ycle 90 % t res - drop debounce t ime for res voltage - drop p rotection 1.5 s internal timing s ection t ct linear o peratio n r ange of c t v lpc =1.5 v 27 30 33 ? s v lpc - op linear o peration r ange of lpc to c harge c t v dd <5 v 0.8 3.4 v v dd >5 v 0.8 4. 0 v v res - op linear o peration r ange of res to discharge c t v dd <5 v 0.8 3.4 v v dd >5 v 0.8 4 .0 v ratio lpc - res ratio between lpc and res 4.65 5 .00 5.35 t lpc - e n minimum lpc time to enable sr switching , v lpc - high >v lpc - en 0.9 1.1 1.3 s t gate - limit t on - sr (n+1)< t gate - limit x t on - sr (n) 105 120 % g reen s ection t green - off c t c apacitor t dis t ime to l eave green m ode f s =65 k hz 4.6 0 5.3 5 6.1 0 s t green - on c t c apacito r t dis t ime to e nter green m ode f s =65 k hz 4.25 4. 8 0 5.35 s t green - time - enter cycle t ime to e nter green m ode c t d ischarge t ime < t green - on 3 times t green - time - leave cycle t ime to l eave green m ode c t d ischarge t ime > t green - off 7 times t green - enter n o g ate s ignal to e nter green m ode ( 3 ) 75 s c ausal f unction s ection t causal once t s - pwm (n+1) > t causal x t s - pwm (n) , sr s tops s witching and e n ter g reen m ode f s = 65 k hz ? 40 k hz 120 % t dead - causal sr t urn - off d ead t ime by c ausal f unction f s =65 k hz 380 580 780 ns t dead - cfr dead time to shrink sr on time cfr ( c ausal f unction r egulator) 1 5 0 ns t dead - re - cfr sr on time n arrowed d own w idth when t dead - cfr t riggered 1.5 ? s i nternal o ver - t emperature p rotection s ection ? t otp internal threshold temperature f or otp ( 3 ) 140 c t otp - hyst h ysteresis temperature for internal otp ( 3 ) 20 c note: 3. guarantee d by d esign .
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 7 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification typical performance characteristics figure 6. turn - on threshold voltage figure 7. turn - off threshold voltage figure 8. start up current figure 9. operating current figure 10. operating current in green mode figure 11. gate output clamping voltage
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 8 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification typical performa nce characteristics (continued) figure 12. lpc source current figure 13. lpc lower clamp voltage figure 14. t hreshold v oltage of v res figure 15. ratio between lpc and res figure 16. minimum lpc enable time figure 17. m aximum period between lpc rising e dge to gate falling e dge
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 9 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification functional description figure 18. typical waveforms of linear - predict timing control in ccm and dcm/qr flyback linear predict timing control the sr mosfet turn - off timing is determined by linear - predict timing control and the operation principle is based on the volt - second balance theorem . the volt - second balance theorem states that the inductor average voltage is zero during a switching period in steady state, so the charg e voltage and charg e time product is equal to the discharg e voltage and discharg e time product. in flyback converters, the charg e voltage on the magnetizing inductor is input voltage ( v in ) , while the discharg e voltage is nv out , as the typical waveforms show in figure 18 . t he following equation can be drawn: ( 1 ) where t pm,on is inductor charg e time and t l,dis is inductor discharge time . f an 6204a uses the lpc and res pin s with two sets of voltage divider s to sense det voltage ( v det ) and output voltage (v out ) , respectively ; so v in /n , t pm.on , and v out can be obtained. as a result, t l,dis , which is the on - time of sr mosfet, can be predicted by e quation ( 1 ) . as shown in figure 18 , t he sr mosfet is tur ned on when the sr mosfet body diode starts conducting and det voltage drops to zero. t he sr mosfet is turned off by linear - predict timing control. circuit realization the linear - predict timing - control circuit generates a replica (v ct ) of magnetizing curr ent of flyback transformer using internal timing capacitor (c t ) , as shown in figure 19 . using the internal capacitor voltage, the inductor discharge time ( t l.dis ) can be detected indirectly , as shown in figure 18 . when c t is discharged to zero, the sr controller turns off the sr mosfet. v o u t v d e t i m v i n / n p r i m a r y m o s f e t v g s s y n c h r o n o u s r e c t i f i e r m o s f e t v c t v l p c t p m . o n i d s i s r / n v i n / n + v o u t t l . d i s t c t . d i s b o d y d i o d e o f s r m o s f e t b o d y d i o d e o f s r m o s f e t 0 . 0 5 v o u t 0 . 8 3 v l p c - h i g h v l p c - h i g h i d s p r i m a r y m o s f e t i m , a v i m , m a x i m , m i n v o u t v d e t i m v i n / n p r i m a r y m o s f e t v g s s y n c h r o n o u s r e c t i f i e r m o s f e t v c t v l p c t p m . o n i d s i s r / n v i n / n + v o u t t l . d i s t c t . d i s b o d y d i o d e o f s r m o s f e t b o d y d i o d e o f s r m o s f e t 0 . 0 5 v o u t 0 . 8 3 v l p c - h i g h v l p c - h i g h b l a n k i n g t i m e ( t l p c - e n ) i m , m a x i m , m i n .. in pm on out l dis v t n v t ? ? ? ?
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 10 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification figure 19. simplified linear - predict block the voltage - second balance equation for the primary - side inductance of the flyback converter is gi ven in e quation ( 1 ) . i nductor current discharge time is given as : ( 2 ) t he voltage scale - down ratio between res and lpc is defined as k below : ( 3 ) d uring t pm.on , the charge current of c t is i chr - i dichr , while during t l . dis , the discharge current is i dichr . as a result, t he current - second balance equation for internal timing capacitor (c t ) can be derived from : ( 4 ) therefore , the discharge time of c t is given as : ( 5 ) when the voltage scale - down ratio between res and lpc (k) is five ( 5 ) , the discharge time of c t ( t ct.dis ) is the same as inductor current discharge time ( t l.dis ). however, considering the tolerance of voltage divider resistors and internal circuit, the scale - down ratio (k) should be larger than five ( 5 ) to guarantee that t ct. dis is shorter than t l.dis . it is typical to set k around 5 ~ 5.5 . referr ing to figure 18 ; when lpc voltage is higher than v lpc - en over a blanking time (t lpc - en ) and lower than v lpc - th - high (0.05 v out ), then sr mosfet can be trig gered. therefore, v lpc - en must be lager than v lpc - th - high or the sr mosfet can not be turned on. when designing the voltage divider of lpc, r 1 and r 2 should be considered as: ( 6 ) on the other ha nd, the linear operation ranges of lpc and res (1~4 v) should be considered as: ( 7 ) ( 8 ) ccm o peration t he typical waveform s of c cm operation in steady state are shown as figure 18 . w hen the primary - side mosfet is turned on , the energy is stored in l m . d uring the on - time of the primary - side mosfet ( t pm.o n ) , the magnetizing current ( i m ) in creases linearly from i m,min to i m,max . meanwhile, internal timing capacitor (c t ) is charged by current source ( i chr - i dichr ) proportional to v in , so v ct also increases linearly. when the primary - side mosfet is turned off, the energy stored in l m is release d t o the output. du ring the inductor discharge time ( t l.dis ) , the magnetizing current ( i m ) decreases linearly from i m,max to i m,min . at the same time, the internal timing capacitor (c t ) is discharged by current source (i dischr ) proportional to v out , so v ct also decreases linearly. to guarantee the proper operation of sr, it is important to turn off sr mosfet just before sr current reaches i m,min so that the body diode of sr mosfet conducts naturally during the dead time . dcm / qr o peration in dcm / qr oper ation, when primary - side mosfet is turned off, the energy stored in l m is fully released to the output at the turn - off timing of primary - side mosfet. therefore, the det voltage continues resonating until the primary - side mosfet is turned on , as depicted in figure 18 . while det voltage is resonating, det voltage and lpc voltage drop to zero by resonance, which can trigger the turn - on of the sr mosfet. to prevent fault triggering of the sr mosfet in dcm operation, blanking time is introduced to lpc voltage. the sr mosfet is not turned on even when lpc voltage drops below 0.05 v out unless lpc voltage stays above 0. 83 v lpc - high longer than the blanking time ( t lpc - en ). the turn - on timing of the sr mofet is inhibited by gate inhibit ti me (t inhibit ) , once the sr mosfet turn s off , to prevent fault triggering. mwsaver ? technology green - mode o peration to minimize the power consumption at light - load condition, the sr circuit is disabled when the load decreases. as illustrated in figure 20 , the discharge times of inductor and internal timing capacitor decrease as load decreases. if the discharge time of the internal timing capacitor is shorter than t green - on (around 4. 8 s) for more than three cycl es, the sr circuit enters green mode . once f an 6204a enters green mode , the sr mosfet stops switching and the major internal block is shut down to further reduce operating current of the sr controller . in green mode , the operating current reduces to 1.1 m a. this allows power supplies to meet the most stringent power conservation requirements. when the discharge time of the internal capacitor is longer than t green - o ff (around 5 . 3 5 s) for more than seven cycles, the sr circuit is enabled and resumes the norma l operation , as shown in figure 21 . .. 5 ( ( ) ) in out out pm on out ct dis v v v t v t kn ? ? ? ? ? ? . . 5 ( ( ) ) in out out pm on ct dis out v v v t kn t v ? ? ? ? ? . 2 12 0.83 ( ) 0.05 0.3 in min out out v r vv r r n ? ? ? ? ? ? . 2 12 ( ) 4 in max out v r v r r n ? ? ? ? 4 4 3 4 ? ? ? out v r r r 5 a / v v c t 8 l p c 1 a / v s r q q + - c t i c h r i d i s c h r v l p c - t h 7 r e s v c t t u r n o f f s r g a t e t u r n o n s r g a t e a t t h e f a l l i n g e d g e v l p c s r g a t e r 1 r 2 r 3 r 4 v d e t v o u t . . in pm on l dis out vt t nv ? ? ? ? ? ? ? 4 3 4 2 1 2 / / r r r k r r r ? ? ?
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 11 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification figure 20. entering green mode figure 21. resuming normal operation causal function causal f unction is utilized to limit the time i nterval (t sr - max ) from the rising edge of v lpc to the falling edge of the sr gate . t sr - max is limited to 97% of previous switching period, as shown in figure 22 . when the system operates at fixed frequency , whether voltage - seco nd balance theorem can be applied or not , causal function can guarantee reliable operation. figure 22. causal function operation fault causal timing protection fault c ausal t iming p rotection is utilized to disable the sr gate under some abnormal conditions. once the switching period (t s - pwm (n)) is longer than 120% of previous switching period (t s - pwm (n - 1)), sr gate is disabled and enter s green mode , as shown in figure 23 . since the rising edge of v lpc among s witching periods (t s - pwm ) is tracked for causal function, the accuracy of switching period is important. therefore, if the detected switching period has a serious variation under some abnormal conditions, the sr gate should be terminated to prevent fault t rigger. figure 23. fault causal timing protection gate expand limit protection gate expand limit p rotection controls on - time expansion of the sr mosfet . once the discharge time of the internal timing capacitor (t dis.ct ) is longer than 1 15 % of previous on time of the sr mosfet (t on - sr (n - 1)) ; t on - sr (n) is limited to 1 15 % of t on - sr (n - 1), as shown in figure 24 . when output load changes rapidly from light load to heavy load, voltage - second balance theorem may not be applied . i n this transient state , g ate expand l imit protection is activated to prevent overlap between sr gate and pwm gate . figure 24. gate expand limit protection res voltage drop protection res voltage drop p rotection prevent s v res drop ping too much within a cycle. the v res is sampled as a reference voltage , v res , on v lpc rising edge . o nce v res drops below 90% of v res for longer than a debounce time (t res - drop ) , the sr gate is turned off immediately, as shown in figure 25 . when output voltage drops rapidly within a switching cycle, voltage - second balance may not be applied, res d ropping p rotection is activated to prevent overlap. figure 25. v res dropping protection i m s r g a t e 4 . 8 s 4 . 8 s 4 . 8 s 3 t i m e s g r e e n m o d e n o r m a l m o d e i m s r g a t e 5 . 3 5 s . 7 t i m e s 5 . 3 5 s 5 . 3 5 s g r e e n m o d e n o r m a l m o d e v l p c s r _ g a t e v c t t p 1 s r o n - t i m e t p 1 r i s i n g e d g e r i s i n g e d g e t s - p w m t s r - m a x = t s - p w m * 9 7 % s r g a t e i s t u r n e d o f f b y c a u s a l f u n c t i o n v l p c s r _ g a t e d i s a b l e s r - g a t e & e n t e r g r e e n m o d e t s - p w m ( n - 1 ) t s - p w m ( n ) > 1 . 2 x t s - p w m ( n - 1 ) t o n - s r ( n - 1 ) v l p c s r _ g a t e v c t s r - g a t e i s t u r n e d o f f b y g a t e l i m i t p r o t e c t i o n t o n - s r ( n ) = t o n - s r ( n - 1 ) * 1 1 5 % t d i s . c t ( n ) t d i s . c t ( n - 1 ) v l p c s r _ g a t e v r e s v r e s s r - g a t e i s t u r n e d o f f i m m e d i a t e l y t r e s - d r o p 0 . 9 * v r e s
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 12 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification lpc pin open / short protection lpc - open protection: if v lpc is higher than v lpc - dis (4.2 v) for longer than debounce time t lpc - high , fan 6204a stops switching immediately and enter s green mode . v lpc is cl amped at 6 v to avoid lpc pin damage. lpc - short protection: if v lpc is pulled to ground and the charging current of timing capacitor (c t ) is near zero, so that sr gate is not output. res pin open / short protection res - open protection: if v res is pulled to high level , the gate signal is extremely small and fan 6204a en ter s green mode . in addition, v res is clamped at 6 v to avoid res pin damage . res - short protection: if v res is lower than v res - en (0.7 v) for longer than debounce time t res - low , FAN6204A stops switching immediately and enter s green mode . under - voltage lo ckout (uvlo) the power on and off v dd threshold voltage s are fixed at 4.8 v and 4.5 v , respectively . with an ultra - low v dd threshold voltage , f an 6204a can be used in various output voltage application s . v dd p in over - voltage protection (ovp) o ver - voltage c onditions are usually caused by an open feedback loop. v dd over - voltage protection prevent s damage on the sr mosfet . when the voltage on vdd pin exceeds 2 7 .5 v, the sr controller stop s switch ing the sr mos fet . over - temperature protection (otp) t o prevent sr gate from fault trigger ing in high temperature s , i ntern al over - temperature protection is integrated in fan 6204a . once the temperature is over 140 c , sr gate is disabled until the temperature drops below 120 c .
? 20 15 semiconductor components indu stries, llc. www.on semi.com FAN6204A ? rev. 1. 1 13 fan6204 a mwsaver ? synchronous rectification controller for flyback and forward freewheeling rectification physical dimensions figure 26. 8 - pin , small out line package (sop) 8 0 see detail a notes: a) this package conforms to jedec ms-012, variation aa. b) all dimensions are in millimeters. c) dimensions do not include mold flash or burrs. d) landpattern standard: soic127p600x175-8m e) drawing filename: m08arev16 land pattern recommendation seating plane c gage plane x 45 detail a scale: 2:1 pin one indicator 4 8 1 b 5 a 5.60 0.65 1.75 1.27 6.000.20 3.900.10 4.900.10 1.27 0.420.09 0.1750.075 1.75 max 0.36 (0.86) r0.10 r0.10 0.650.25 (1.04) option a - bevel edge option b - no bevel edge 0.25 c b a 0.10 0.220.03 (0.635)
? 20 15 semiconductor components industries, llc. www.on semi.com FAN6204Amx ? rev. 1. 1 14 fan6204 amx mwsaver ? synchronous rectification controlle r for flyback and forward freewheeling rectification on semiconductor and the on semiconductor logo are trademarks of semiconductor components industries, llc dba on semiconductor or its subsidiaries in the united states and/or other countries. on semiconductor owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. a listing of on semiconductors product/pate nt coverage may be accessed at www.onsemi.com/site/pdf/patent - marking.pdf. on semiconductor reserves the right to make changes without further notice to any products herein. on semiconductor makes no warranty, representation or guarantee regard ing the suit ability of its products for any particular purpose, nor does on semiconductor assume any liability arising out of the application or use of any product or ci rcuit, and specifically disclaims any and all liability, including without limitation special, cons equential or incidental damages. buyer is responsible for its products and applications using on semiconductor products, including compliance with all laws, regulations and safety requirements or standards, regardless of any support or applications informa tion provided by on semiconductor. typical parameters which may be provided in on semiconductor data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. all operating parameters, including t ypicals must be validated for each customer application by customers technical experts. on semiconductor does not convey any license under its patent rights nor the rights of others. on semiconductor products are not designed, intended, or authorized for use as a critical component in life support systems or any fda class 3 medical devices or medical devices with a same or simi lar classification in a foreign jurisdiction or any devices intended for implantation in the human body. should buyer purchase or use on semiconductor products for any such unintended or unauthorized application, buyer shall indemnify and hold on semiconductor and its officers, employees, subsidiaries, affiliates, and distr ibutors harmless against all claims, costs, damages, and expe nses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated w ith such unintended or unauthorized use, even if such claim alleges that on semiconductor was negligent regarding the design or man ufacture of the part. on semiconductor is an equal opportunity/affirmative action employer. this literature is subject to all applicable copyright laws and is not for resale in any manner. publication ordering information literature fulfillment: literature distribution center for on semiconductor 19521 e. 32nd pkwy, aurora, colorado 80011 usa phone : 303 - 675 - 2175 or 800 - 344 - 3860 toll free usa/canada fax: 303 - 675 - 2176 or 800 - 344 - 3867 toll free usa/canada email : orderlit@onsemi.com n. american t echnical support : 800 - 282 - 9855 toll free usa/canada. europe, middle east and africa technical support : phone: 421 33 790 2910 japan customer focus center phone: 81 - 3 - 5817 - 1050 on semiconductor website : www.onsemi.com order literature : http://www.onsem i.com/orderlit for additional information, please contact your local sales representative
www. onsemi.com 1 on semiconductor and are trademarks of semiconductor components industries, llc dba on semiconductor or its subsidiaries i n the united states and/or other countries. on semiconductor owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property . a listing of on semiconductor?s product/patent coverage may be accessed at www.onsemi.com/site/pdf/patent ? marking.pdf . on semiconductor reserves the right to make changes without further notice to any products herein. on semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does o n semiconductor assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including wi thout limitation special, consequential or incidental damages. buyer is responsible for its products and applications using on semiconductor products, including compliance with all laws, reg ulations and safety requirements or standards, regardless of any support or applications information provided by on semiconductor. ?typical? parameters which may be provided in on semiconductor data sheets and/or specifications can and do vary in dif ferent applications and actual performance may vary over time. all operating parameters, including ?typic als? must be validated for each customer application by customer?s technical experts. on semiconductor does not convey any license under its patent rights nor the right s of others. on semiconductor products are not designed, intended, or authorized for use as a critical component in life support systems or any fda class 3 medical devices or medical devices with a same or similar classification in a foreign jurisdiction or any devices intended for implantation in the human body. should buyer purchase or use on semicondu ctor products for any such unintended or unauthorized application, buyer shall indemnify and hold on semiconductor and its officers, employees, subsidiaries, affiliates, and distrib utors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that on semiconductor was negligent regarding the design or manufacture of the part. on semiconductor is an equal opportunity/affirmative action employer. this literature is subject to all applicable copyright laws and is not for resale in any manner. publication ordering information n. american technical support : 800 ? 282 ? 9855 toll free usa/canada europe, middle east and africa technical support: phone: 421 33 790 2910 japan customer focus center phone: 81 ? 3 ? 5817 ? 1050 www.onsemi.com literature fulfillment : literature distribution center for on semiconductor 19521 e. 32nd pkwy, aurora, colorado 80011 usa phone : 303 ? 675 ? 2175 or 800 ? 344 ? 3860 toll free usa/canada fax : 303 ? 675 ? 2176 or 800 ? 344 ? 3867 toll free usa/canada email : orderlit@onsemi.com on semiconductor website : www.onsemi.com order literature : http://www.onsemi.com/orderlit for additional information, please contact your local sales representative ? semiconductor components industries, llc

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