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shenzhen lize electronic technology co., ltd specification L2269 current mode pwm controller version 1.0 reserves the right to chan ge this documentation without prior notice
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 2 of 13 L2269 current mode pwm controller frequency shuffling description L2269 is highly integrated current mode pwm control ic optimized for high performance, low standby power and cost effective offline flyblack converter applications in sub 80w range. pwm switching frequency at normal operation is externally programmable to tight range. at no load or light load condition, the ic operates in extended ?bur st mode? to minimize switching loss.lower standby power and higher conversion efficiency in thus achieved. vdd low startup current and low operating current contribute to a reliable power on startup design with L2269.a large value resistor could thus be us ed in the startup circuit to minimize the standby power. L2269 offers complete protection cov- erage with automatic self- recovery feature inc- luding cycle-by-cycle current limiting (ocp), over temperature protection(otp),vdd over voltage clamp and under voltage lockout (uv lo).the gate output is clamped to maximum 18v to protect the power mosfet. features z proprietary frequency shuffling technology for improved emi performance. z external programmable pwm switching frequency. z leading edge blanking on current sense input. z internal synchronized slope compensation . z extended burst mode control for improved efficiency and minimum standby power design z low vdd startup current and low operating current. z gate output maximum voltage clamp 18v. z cycle-by-cycle current limiting, built-in adaptive current peak regulation z power on soft-start, programmable cv and cc regulation z vdd under voltage lockout with hysteresis(uvlo),ovp,ocp,olp, clamp vdd, applications z digital cameras charger z power adaptor z set_top box power supplies z open_frame smps z battery charger
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 3 of 13 L2269 current mode pwm controller frequency shuffling application circuit pin assignment & marking information ordering information part number package L2269-si sop-8 L2269-di dip-8
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 4 of 13 L2269 current mode pwm controller frequency shuffling pin description pin number symbol type description 1 gnd p ground. 2 fb i feedback input pin.the pwm duty cycle is determined by voltage level into this pin and sense pin input. 3 vin i connected through a large va lue resistor to rectified line input for startup ic supply gnd and line voltage sensing. 4 ri i internal oscilla tor frequency setting pin. 5 rt i temperature sensing intp ut pin,connected through a ntc resistor to gnd. 6 sense i current sense intput pin. connected to mosfet current resistor ode. 7 vdd p chip dc power supply pin 8 gate o totem-pole gate diver output for the power mosfet recommended out power input:230vac15% input:85-264vac product adapter adapter L2269 100w 90w
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 5 of 13 L2269 current mode pwm controller frequency shuffling block diagram absolute maximum rating parameter value unit vdd/vin supply voltage 30 v vdd zener clamp voltage vdd clamp +0.1 k ? vdd clamp continuous current 10 ma vfb input voltage -0.3 to 7 v vsense input voltage to sense pin -0.3 to 7 v vrt input voltage to rt pin -0.3 to 7 v vri input voltage to ri pin -0.3 to 7 v operating ambient temperature -20 to 85 min/max operating junction temperature -55 to 150
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 6 of 13 L2269 current mode pwm controller frequency shuffling recommended operating conditions symbol parameter min. max. unit vdd supply voltage vcc 11 29 v ri ri resistor value 24 31 kohm t a operating ambient temperature -20 85 esd information s y mbol parameter test conditions min. typ. max. unit hbm human bodymodel on all pins except vin and vdd mil-std 3 kv mm machine model on all pins jedec-std 250 v electrical characteristics (t a = 25 , if not otherwise noted) value unit symbol parameter conditions min. typ. max supply voltage (vdd pin) idd_startup vdd start up current vdd=12.5v ri=24k 6 10 ua idd vdd current vdd=18v ri=24k ? , fb=3.6v 2.3 ma uvlo (enter) vdd under voltage lockout enter 9.5 10.5 11.5 v uvlo(exit) vdd under voltage lockout exit 15.5 16.5 17.5 v ovp(enter) vdd over voltage protection enter 24 26.5 27.5 v ovp(exit) vdd over voltage protection exit 22 24 25.5 v vdd_clamp vdd zener clamp voltage idd=10ma 29 30 31 v td_ovp vdd ovp debounce time 80 us voltage feedback (fb pin) avcs pwm input gain vfb/ vsense 2.8 v/v vfb_open vfb open loop voltage 5.8 v vfb_burst burst mode voltage 1.7 v ifb_short fb pin short current short fb pin to gnd and measure current 1.2 ma vth_pl power limiting fb threshold voltage iout= 10ma 4.5 v
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 7 of 13 L2269 current mode pwm controller frequency shuffling td_pl power limiting debounce time 64 ms current sense(cs pin) t_blanking leading edge blanking time 250 ns zsense_in input impedance 30 k ? vth_oc_0 current limiting threshold voltage at no compensation i(vin)= 0 ua 0.9 v vth_oc_1 current limiting threshold voltage at compensation i(vin)= 150 ua 0.81 v oscillator(rt pin) fosc normal oscillation frequency ri=24k ? 60 65 70 khz f_temp frequency temperature stability ta -20 to 100 vdd=16v,ri=24k ? 2 % f_vdd frequency voltage stability vdd=12v to 25v ri=24k ? 2 % ri_range operating ri range 12 24 60 k ? vri_open ri open load voltage 2 v fosc_bm burst mode base frequency 25 khz dc_max maximum duty cycle vdd=18v, fb=3v sense=0v 80 % f_osc frequency modulation range /base frequency -5 +5 % gate drive output(out pin) vol output low level vdd=18v,io=-20ma 0.3 v voh output high level vdd=18v,io=20ma 11 v v_clamp output clamp voltage level 18 v t_r output rising time vdd=18v,cl=1nf 110 ns t_f output falling time vdd=18v,cl=1nf 40 ns over temperature protection i_rt output current of rt pin 70 ua v_otp otp threshold voltage 0.65 v v_otp_off otp recovery threshold voltage 0.8 v t_otp otp de-bounce time 100 us
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 8 of 13 L2269 current mode pwm controller frequency shuffling typical performance characteristics
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 9 of 13 L2269 current mode pwm controller frequency shuffling application information the L2269 is a highly integrated pwm controller ic optimized for offline flyback converter applications. the extended burst mode control gr eatly reduces the standby power consumption and helps the design easily meet the intern ational power conservation requirements. startup current and start up control startup current of L2269 is designed to be ve ry low so that vdd coul d be charged up above uvlo(exit) threshold level and device starts up quick ly. a large value startup resistor can therefore be used to minimize the power loss yet reliable st artup in application. for a typical ac/dc adaptor with universal input range design, a 2 m ? , 1/8 w startup resistor coul d be used together with a vdd capacitor to provide a fast startup a nd yet low power dissipation design solution. operating current the operating current of L2269 is low at 2.3m a. good efficiency is achieved with L2269 low operating current together with extended burst mode control schemes. frequency shuffling for emi improvement the frequency shuffling/jittering (switching fr equency modulation) is implemented in L2269. the oscillation frequency is modulated with a inte rnally generated random s ource so that the tone energy is evenly spread out.the spread spectrum minimizes the conduction band emi and therefore eases the system design in mee ting stringent emi requirement. burst mode operation at zero load or light load condition, most of the power dissipation in a switching mode power supply is from switching loss on the mosfet ransis tor, the core loss of the transformer and the loss on the snubber circuit. the ma gnitude of power loss is in pr oportion to the number of swit- -ching events within a fixed period of time. re ducing switching events leads to the reduction on the power loss and thus conserves the energy. L2269 self adjusts the switching mode according to the loading condition. at from no load to light/medium load condition, the fb input drops be low burst mode threshold level (1.8v). device
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 10 of 13 L2269 current mode pwm controller frequency shuffling enters burst mode control. the gate drive outpu t switches only when vdd voltage drops below a preset level and fb input is activ e to output an on state. otherwis e the gate drive remains at off state to minimize the switching loss thus reduce the standby power consumption to the greatest extend. the nature of high frequency switching also reduces the audio noise at any loading conditions. oscillator operation a resistor connected between ri and gnd sets th e constant current source to charge/discharge the internal cap and thus the pwm oscillator freq uency is determined. the relationship between ri and switching frequency follows the below equati on within the specified ri in kohm range at nominal loading operational condition. fosc = 1560/ri(k ) ( khz) current sensing and leading edgeblanking cycle-by-cycle current limiting is offered in L2269 current mode pwm control. the switch current is detected by a sense resistor into the se nse pin. an internal leading edge blanking circuit chops off the sense voltage spike at initial mosfet on state due to snubber diode reverse recovery so that the external rc filtering on sense input is no longer required. the current limit comparator is disabled and thus cannot turn off the ex ternal mosfet during the blanking period. pwm duty cycle is determined by the current sense input voltage and the fb input voltage. internal synchronized slope compensation built-in slope compensation circuit adds voltage ramp onto the current sense input voltage for pwm generation. this greatly improves the clos e loop stability at ccm and prevents the sub-harmonic oscillation and thus re duces the output ripple voltage. over temperature protection a ntc resistor in series with a regular re sistor should connect between rt and gnd for emperature sensing and protection. ntc resist or value becomes lower when the ambient temperature rises. with the fixed internal current irt flowing through the re sistors, the voltage at rt pin becomes lower at high temperature. the in ternal otp circuit is tr iggered and shutdown the
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 11 of 13 L2269 current mode pwm controller frequency shuffling mosfet when the sensed input voltage is lower than vth_otp. gate drive L2269 gate is connected to the gate of an external mosfet for power switch control. too weak the gate drive strength results in highe r conduction and switch lo ss of mosfet while too strong gate drive output compromises the emi. good tradeoff is achieved through the built-in totem pole gate dr ive design with right output strength and dead time control. the low idle lo ss and good emi system desi gn is easier to achieve with this dedicated control scheme. an internal 18v clamp is added for mosfet gate protection at higher than expected vdd input. protection controls good system reliability is achie ved with L2269?s rich protecti on features including cycle-by- cycle current limiting (ocp), over load protecti on (olp), over temperature protection (otp), on chip vdd over voltage protection (ovp, op tional) and under voltage lockout (uvlo). the ocp threshold value is self adjusted lower at higher current into vin pin. this ocp threshold slope adjustment helps to compensate the increas ed output power limit at higher ac voltage caused by inherent over-current sensing and control delay. a constant output power limit is achieved with recommended ocp compensation scheme on L2269.a t output overload condition, fb voltage is biased higher. when fb input exceeds power limit threshold valu e for more than 80ms, control circuit reacts to turnoff the power mosfet. similarly, control circuit shutdowns the power mosfet when an over temperature condition is detected.L2269 resumes the operation when temper ature drops below the hysteresis value.vdd is supplied with transformer auxiliary winding output. it is clamped when vdd is higher than 35v. mosfet is shut down when vdd drops below uvlo(enter) limit and device enters power on startup sequence thereafter
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 12 of 13 L2269 current mode pwm controller frequency shuffling package information sop-8
shenzhen lize electronic technology co., ltd reserves the right to change this documentation without prior notice page 13 of 13 L2269 current mode pwm controller frequency shuffling dip-8

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