2014. 8. 13 1/6 semiconductor technical data revision no : 1 general description the KIC3522F is a single stage primary side regulation (psr) power factor correction (pfc) controller, specially designed for led driver. the device adopts constant on time operation to achieve high power factor. the KIC3522F provides accurate constant current control and operates in boundary conduction mode (bcm) with high efficiency. the device adopts primary side regulation eliminating the opto-couple, secondary feedback control and loop compensation for reducing design and cost. the KIC3522F provides completed protections such as short led protection, open led protection and over temperature protection, etc. features h psr flyback topology h boundary conduction mode h low start current h leading edge blanking h constant on-time control h vcc over voltage protection. h vcc under voltage lockout h over temperature protection. h cycle by cycle current limiting h peak current compensation h short led protection and open led protection applications h led lamp h led illuminance with ac input flp-8 0.20+0.1/-0.05 p t 1.27 u 0.1 max millimeters 0.4 0.1 0.15+0.1/-0.05 4.85 0.2 b2 g h l d a b1 dim 6.02 0.3 1.63 0.2 0.65 0.2 3.94 0.2 + _ + _ + _ + _ + _ + _ g h b1 b2 1 4 5 8 a p d l t u KIC3522F analog cmos integrated circuits c3522f lot no. (top view) n.c n.c v cc drv comp fb cs gnd type name pin configurations
2014. 8. 13 2/6 KIC3522F revision no : 1 functional block diagram pin description clamp clamp v_ovp zcd led_s fb_o fb_ovp gm 0.1v 0.2v uvlo 16v/8v fb 2 cs 3 v cc 6 dr 5 gnd 4 comp 1 r s q leb max_toff min_toff min_t cc module pfc module cs_o cs_pl drive pin no. function i/o description 1 comp i/o rc loop compensation pin, output of transconductance amplofier 2 fb i feedback voltage input pin 3 cs i current sense pin 4 gnd i/o ground 5 dr o drive pin 6 v cc i/o power supply 7 n.c - n.c 8 n.c - n.c KIC3522F k i c 3 5 2 2 f 8 6 2 5 nc v cc fb dri 3 cs 4 gnd 1 comp 7 nc s1 rs na cin ac vin t np ns ds co typical application circuit
2014. 8. 13 3/6 KIC3522F revision no : 1 absolute maximum ratings electrical characteristics (unless otherwise specified, v cc =18v, t amb =25 ? ) characteristics symbol test condition min typ max unit supply voltage section operating voltage v cc after ic starts 9 - 18 v turn-on threshold v ccon - 14.4 16 17.6 v turn-off voltage v ccoff - 6.9 8.0 9.1 v clamp voltage v z i cc = 20ma - 27 - v v cc over voltage threshold v cc_ovp - 21.4 23 24.6 v start-up current i start v cc = 15v 0 3 10 a operating current i op - 300 500 800 a fb feedback section ovp threshold value v fbovp - 1.38 1.46 1.54 v short-circuit detect voltage v sht - 0.24 0.29 0.34 v short-circuit detect timing t sht after 768 switching periods - 768 - - zero-crossing detection v zcs - 0.17 0.2 0.23 v fb open loop switching times n - - 768 - - dynamitic characteristic section leading-edge blanking time t leb - 0.6 0.75 0.9 s max. on time t onmax comp connected to 4v via 20k 24 33 42 s max. off time t offmax - 25 34 43 s min. off time t offmin - 3.2 4.2 5.2 s min. period t min - 6.3 8.3 10.3 s current limit section cs peak limit v cspl - 0.49 0.60 0.71 v gm amplifier section cs cc compare point v cscc - 0.097 0.100 0.103 v characteristics symbol rating units supply voltage v cc -0.3 ~ 23 v analog pin voltage - -0.3 ~ 5.5 v power dissipation *note ) p d 600 mw junction temperature range t j -40 ~ 150 ? storage temperature range t stg -55 ~ 150 ? *note ) dimensions 40mm ? 40mm (glass epoxy (fr-4), thickness 1.6mm)
2014. 8. 13 4/6 KIC3522F revision no : 1 characteristics symbol test condition min typ max unit drive section dr rising time t r c=1nf 100 200 400 ns dr falling time t f c=1nf 40 60 80 ns dr high clamp voltage v drc - 16 17.5 19 v peak drive source current i srcpk c=1nf 0.2 - - a peak drive sink current i snkpk c=1nf 0.7 - - a dr high level v drh i source =25ma 14 15.6 - v dr low level v drl i sink =20ma - 0.3 0.5 v otp (over temperature protection) section otp temperature detection t sd - - 150 - ? otp temperature hysteresis t sdhys - - 20 - ?
the KIC3522F is a single stage primary side regulation (psr) power factor correction (pfc) controller, specially designed for led driver. the device adopts constant on time operation to achieve high power factor. the KIC3522F provides accurate constant current control and operates in boundary conduction mode (bcm) with high efficiency. the device adopts primary side regulation eliminating the opto-couple, secondary feedback control and loop compensation for reducing design and cost. the KIC3522F provides completed protections such as short led protection, open led protection and over temperature protection, etc. 1. start-up and under voltage lockout after ac supply is powered on, the capacitor connected to pin vcc is charged by ac supply through a start resistor. once vcc voltage rises up to 16v, the circuit starts to work. vcc voltage will be pulled down by internal consumption of ic until the auxiliary winding of flyback transformer could supply enough energy to maintain vcc voltage above 8v. if the protection occurs, the output of circuit is off, vcc voltage starts to decrease. if vcc voltage is decreased to 8v, the capacitor connected to pin vcc is recharged through start resistor. 2. drive circuit drive circuit is power by v cc . when dr $ 1, mosfet is on; when dr $ 0, mosfet is off. t leb $ 0.75 s is set to avoid the burr which will cause error at the turn-on transient of mosfet. 3. peak current detection and sense when mosfet is on, the primary current, which is detected by sense resistor, increases linearly. if this current exceeds the threshold value 0.6v, the current limit comparator acts to turn off mosfet and dr $ 0. when it is normal, primary peak current is i pk , and the secondary diode on time detected at fb is t off1 , hence, the output current is given by: i out = 0.5 !? n !? i pk !? t off1 /t where, n is the primary/secondary turns ratio. i pk !? t off1 /t is calculated in integral mode, and i pk !? t off1 /t=v cscc /r sen is realized through loop control. where, rsen is the sense resistor. that is, i out = 0.5 !? n !? v cscc /r sen the output of error amplifier comp is used for switch on control. when the on time is up, dr $ 0, mosfet is off. 4. boundary conduction mode the pin fb detects the voltage across the auxiliary winding by a resistor divider. when the secondary current turns to zero, fb voltage starts to decrease. if fb voltage is decreased to 0.2v, the mosfet would be turned on. 5. vcc over voltage protection and open led protection the output voltage is reflected by the auxiliary winding voltage of the flyback transformer, and both pin fb and pin vcc provide over voltage protection function. when vcc voltage exceeds 23v, or fb voltage exceeds 1.46v, the over voltage protection is triggered and the ic will discharge, vcc voltage start to decrease. if vcc voltage is decreased to 8v, the capacitor connected to pin vcc is recharged through start resistor. if the over voltage condition still exists, the system will operate in hiccup mode. 2014. 8. 13 KIC3522F revision no : 1 5/6 function description v cc powered by resistor powered by auxiliary winding and resistor powered byresistor v start v stop i cc 0 0 t t
6. over temperature protection if the circuit is over temperature, the output is shut down to prevent the circuit from damage. the over temperature protection has the hysteresis characteristic. the temperature should be decreased lower than the threshold temperature by 20 ? c for normal operation. this is adopted to avoid frequently change between normal and protection modes. 7. leb short-circuit protection when led is short-circuit and held for 768 periods, the protection acts and the circuit restarts after the protection. 2014. 8. 13 6/6 KIC3522F revision no : 1
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