WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 c o p y r igh t @ w i n s em i microelectronics c o . , lt d . , a l l ri g h t r e s er v ed . current current current current mode mode mode mode pwm pwm pwm pwm controller controller controller controller fe a t ures burst mode function low startup current (6. 5 ua) low operating current (2 . 3ma) built-edge blanking built-in synchroni z ed slope compensation current mode e x ternal programmable pwm s w itching frequency by-cycle current limit protection (ocp) vdd over-voltage clamping protection low voltage shut do w n function (uvlo) gate drive output v o ltage clamp (18v) frequency j itter feature constant output po w er limit overload protection (olp) w o rk does not produce audio noise applic a t ions of fl ine a c /dc flyback converter f or po w er a daptor open-frame smps battery charger set- t o p box po w er suppl i es typical applic a t ion gerneral description wis2269 is a highly integrated, high performance current mode pwm controller chip. app l y to the po w er adapter and other small and medium-po w er s w itch po w er suppl y . in order to reduce standby po w er consumption to meet the higher standards of environmental protection, the chip provides a pulse mode (burst mode) function, very low starting current and operating current. pulse mode that is in the light load or no load conditions, wis2269 can linearly decrease the s w itching frequency chip, thereby reducing s w itching loss; by optimi z ing the design, wis2269 has a very low starting current and operating current, is not only beneficial to start the circuit design, and the start circuit can be used in high-value startup resisto r , to reduce po w er consumption, improve po w er conversion ef fi cienc y . wis2269 built-in synchroni z ed slope compensation circuit, to pre v ent the pwm controller w hen w o r king in high-duty cycle may have harmonic oscillation. wis2269 side in the current sample input pin edge blanking function built in, can eff e ctively remove the current feedback signal of the glitch. help to reduce the number of e x te r nal components, reducing overall system cost. wis2269 off e rs a variety of comprehensi v e resume protection mode, includ i ng:-by-cycle current limit protection (ocp), over-load protection (olp), vdd over-voltage clamping voltage and low voltage closed (uvlo). which, in order to better protect the e x te r nal mosfet po w er transisto r , the gate dri v e output voltage is clamped at 18 v . wis2269 the totem pole gate drive output using a frequency j itter control technology and soft-s w itching technolog y , can be very good to improve emi pe r formance s w itching po w er supply system. by optimi z ing the design, w hen the chip's operating frequency less than 20khz circumstances, the audio energy can be reduced to a minimum. therefore, the audio can get greatly improved noise per f ormance. wis226 9 -chip can be used as rc c -mode po w er supply linear po w er supply or the best alternative to enhance the overall performance of s w itching po w er supply system, and eff e ctively reduce the system cost. wis2269 wis2269 wis2269 wis2269 tl431 re v . a mar.2010 p02-1
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 2 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance general inform a ti on pin pin pin pin configuration configuration configuration configuration terminal assignments pin name pin no. i/o descri p tion gnd 1 p ground fb 2 i feedback input pin. the input level value and 6-pin to monitor the value of current is indeed common set pwm duty cycle control signal. if the fb terminal of the input voltage is greater than a set set threshold voltage, the internal protection circuit w ill automatically turn off pwm output. vi 3 i through a high resistance of the resistor connected to the rectifier output, start the device into the working condition; w hile the voltage is sampled to generate line voltage compensation. ri 4 i internal oscillator frequency setting pin. a resistor connected bet w een ri and gnd sets the pwm frequenc y . r t 5 i t e mperature monitoring of input pins. by a ntc resistor connected to ground. se n se 6 i current sense input pin. connected to mosfet current sensing resistor node. vdd 7 p chip dc po w er supply pin g a t e 8 o t o tem-pole gate drive output f or the po w er mosfe t . block diagram
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 3 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance recommended oper a t ing conditi o n symbol parameter min max unit v dd vdd supply v o ltage 12 23 v ri ri resistor v a lue 24 k t operating amb i ent t em perature -20 85 absolute maximum r a t ings pin name parameter ratings units v dd v dd pin input voltage 30 v v fb v fb p i n input voltage -0 . 3~7 v v sense v sense pin input voltage -0 . 3~7 v v ri v ri p i n input voltage -0 . 3~7 v v r t v rt p i n input voltage -0 . 3~7 v t j operating junction temperature -20~150 t s storage t e mperature -55~160 vcv v dd dc clamping v o ltage 34 v i cc v dd dc clamping current 10 ma note: more than the limit specified in the table parameters w i ll result in permanent damage to the device. the device is not recommended in these e x treme conditions of w o r k, w o r ki n g conditions in the l imit above w hi c h may a ffe ct device reliabilit y .
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 4 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance electrical characte r istics (tc = 25 c,v dd =16v,r i =25k , u n less other w ise specifi e d )
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 5 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 6 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 7 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 8 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance oper a t ion description the wis2269 is a highly integrated, high per f ormance current mode pwm controller chip. appl i cable to high po w er notebook po w er adapter s w itching po w er supply and s w itching po w er converters. v e ry low starting current and operating current, and light load or no load situations burstmode function, can eff e ctively reduce the s w itching po w er supply system, standby po w er consumption, improve po w er conversion ef fi cienc y . built-in synchroni z ed slope compensation of the feedback pin of the leading edge blanking and other functions can not only reduce the number of s w itching po w er supply system components, but also increase the stability of the system, to avoid the production of harmonic oscillation. wis2269 also off e rs a variety of comprehensive resume protected mode. features functions described as f ollo w s: startup current and start up control startup current of wis2269 is designed to be very low(6.5ua) so that vdd could be charged up above uvlo threshold level and device starts up quickl y . a large value startup resistor can there f ore be used to minimi z e the po w er loss yet pro v ides reliable startup in application. for a c/dc adaptor w ith universal input range design, a 2 m ? , 1/8 w startup resistor could be used together w ith a vdd capacitor to pro v ide a f ast startup and low po w er diss i pation solution. operating current the operating current of wis2269 is low at 2 . 3ma. good ef fi ciency is achieved w ith wis2269 low operating current together w ith e x tended burst mode control features. burst mode at no load or light load conditions, s w itching po w er supply in most of the po w er comes from the mosfet's s w itching losses, trans f ormer core losses and the loss of the buff e r circuit. the si z e and po w er consumption w ithin a certain period of time proporti o nal to the number of mosfet s w itches. reduce the s w itching frequency also reduces po w er consumption, saving energ y . wis2269 built-in burst mode feature that automatically ad j usts according to load s w itch mode. when the system is in no load or light / medium load, fb terminal voltage a t the pulse input mode (burstmode) threshold voltage (1.8v) belo w . according to the j udge based on the device into the pulse mode control. gate driver output voltage only w hen the vdd level below the pre-set value, and the fb input is active cases does the output. other cases, the gate dri v e output to maintain the status of long-off to reduce power consumption, w hich reduces standby po w er consumption. the characteristics of high-frequency s w itch also reduced the audio noise a t w o r k. oscillator operation a resistor connected bet w een ri and gnd sets the constant current source to charge/discharge the internal cap and thus the pwm oscillator frequency is determined. the relationship bet w een ri and s w itching frequency f ollo w s the below equation w ithin the specified ri in kohm range a t nominal load i ng operational condition. curren t sensin g an d leadin g edg e b l ankin g cycle-by-cyc l e current limiting is off e red in wis2269 current mode pwm control. the s w itch current is detected by a sense resistor into the sense pin. an internal leading edge blanking circuit chops off the sense voltage spike a t initial mosfet on state due to snubber diode reverse recovery so that the e x te r nal rc filtering on sense input is no longer required. the current limit comparator is disabled and thus cannot turn off the e x te r nal mosfet during the blanking period. pwm duty cycle is determined by the current sense input voltage and the fb input voltage. i n t erna l synchronize d slop e co m pensatio n bui l t-in slope compensation circuit adds voltage ramp onto the current sense input voltage for pwm generation. this greatly improves the close loop stability a t ccm and prevents the sub-harmonic oscil l ation and thus reduces the output ripple voltage. gate drive wis2269 gate is connected to an e x te r nal mosfet gate for po w er s w itch control. t o o w eak the gate drive strength results i n higher conduction and s w itch loss of mosfet w hile too strong gate drive output compromises the emi. a good tradeoff is achieved through the built-in totem pole gate design w ith right output strength and dead time control. the low id l e loss and good emi system design is easier to achieve w ith this dedicated control scheme. an internal 18v clamp is added f or mosfet gate protection a t higher than e x pected vdd inpu t . over-temperature protection bet w een r t and gnd, and a common thread of a ntc resisto r , can provide temperature sensing and protection. ntc resistance w ith the ambient temperature rises. with a fi x ed internal current flo w s through the resistor i r t , r t pin voltage w ith temperatu r e the rises. within the otp circuit to detect the voltage is less than vth_op then triggered off w hen the mosfet protection controls wis2269 provides comprehensi v e protection f eatures, the system can obtain the highest reliab i l i t y . including by- w eek lim i t protection (ocp), over-load protection (olp), over-temperature protection (otp), on-chip vdd over- voltage protection (ov p , optional), and lo w - v oltage shutdo w n (uvlo). when the er into the vin pin large, ocp threshold value is automatically reduced. ocp threshold slope ad j ustment helps compensate for over-current detection and control of ac voltage delay caused by the increasing of the po w er limit . recommended by wis2269 ocp compensation circuit can obtain constant output po w er limit. wis2269 ocp protection circuitry built-in can detect the duty cycle of pwm control signals, and through the line voltage compensation ensure a continuous ac input voltage range w as constant output po w er limit. f o s c = 1560 r i ( k ? ) ( k h z ) i n the case of output overload, fb bias voltage w as highe r , w hen fb input e x ceeds the po w er limit threshold.
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 9 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance voltage continue to 80ms, the control circuit w ill turn off mosfe t . similarl y , the control circuitry detects over- temperature in the case w ill be closed w hen the mosfe t . wis2269 hysteresis temperature value at a temperatu r e lo w er than a f ter the recover y . vdd output from the trans f ormer provide the sub- w inding. vdd is clamped at 36 v . when vdd below the uvlo threshold time, mosfet is turned of f , the device and then entered on the electronic acti v ation.
WIS2269N8 WIS2269N8 WIS2269N8 WIS2269N8 10 /10 steady, steady, steady, steady, keep keep keep keep you you you you advance advance advance advance sop-8 package dimensi o n
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