ts 1970 2 high power factor corrector led driver 1 / 9 version: a12 sot - 26 description the ts19702 is a highly - integrated, low startup current, average current mode, one cycle control pfc and fixed switching frequency pwm controller . th e s e function s enable the led driver to easily meet the accuracy average led c urrent and high power factor requirements . the integrated functions also include the led short protection, open protection, and internal over temperature protection. the comp pin controls the duty by connected an rc compensation network to ground and formi ng the closed loop feedback control . to protect the external power mosfet from being damaged by supply over voltage, the ts19702 o utput pin voltage is clamped to about 15v . features high power factor by one cycle control accuracy constant current low bom cost linear dimming on dim pin average current / fixed frequency control gate output voltage clamp led open protection (ovp) led short p rotection (scp ) over current p rotection (ocp ) internal otp protection 300ma d riving c apability for output pin applicatio n voltage range: 80v ac ~ 308v ac application e27 , t5, t8 led lighting led lighting applications ordering information part no. package packing ts 19 70 2 cx6 rf g sot - 26 3 k pcs / 7 ?reel note: ??denote for halogen free product absolute maximum rating s ( ta = 25 o c unless otherwise noted ) parameter symbol limit unit supply voltage v c c 30 v compensation voltage v c omp - 0.3 ~ 7 v dimming pin v dim - 0.3 ~ 7 v current sense pin v c s - 0.3 ~ 7 v output pin v out 15 v power dissipation @ t a = 8 5 c p d 250 mw operatin g ambient temperature t opr - 20 ~ +85 o c junction temperature t j +150 o c storage temperature range t stg - 65 ~ +150 o c the rmal resistance - junction to ambient r? ja 250 o c/w esd voltage protection hbm 2 kv mm 200 v pin definition : 1. vcc 2. ground 3. output 4. dimming 5. compensation 6. current sense
ts 1970 2 high power factor corrector led driver 2 / 9 version: a12 electrical characteristics (v cc =15 , t a = 25 , unless otherwise specified.) parameter symbol min. typ. max. unit s upply voltage startup c urrent (v cc =uvlo on - 1v) i start -- 8 15 a operating c urrent (with 1nf load on out pin), vcomp = 2.5v i opr -- 2 3 ma operating c urrent (with 1nf load on out pin), p rotection t ripped (o c p, ovp , scp, otp ) i opr -- 0. 7 1 ma uvlo(off) uvlo off 7 8 9 v uvlo(on) uvlo on 14 15 16 v ovp l evel on v cc p in v ovp 26.5 28 29.5 v ovp de - bounce time t ovp -- 40 -- s v oltage feedback feedback reference voltage v fb 0 .196 0.200 0.204 v tran - conductance -- 120 -- s output sink current i sink -- 12 -- a output source current i source -- 12 -- a c urrent sensing i nput over v oltage protection v in - protect 0.7 0.80 0.9 v open loop voltage, cs pin open v cs -- 5 -- v l eading - e dge b lanking t ime t le -- 410 -- n s delay to output t o - delay -- 100 220 ns s witching frequency switching frequency f sw 42 45 48 khz maximum duty d (max) 90 -- -- % frequency jitter range -- +/ - 4 -- % temp. s tability ( - 40 c ~ 1 25 ?) t em p stb -- -- 6 % voltage s tability (v cc = 11v~25v) v stb -- -- 1 % gate driver output rising t ime, l oad c apacitance =1000pf t rising -- 160 320 n s falling t ime, l oad c apacitance =1000pf t falling -- 80 160 n s vgate - c lamp (vcc= 25v ) v gate -- 13.5 15 v dim input sec tion saturation threshold voltage sat th 3.0 -- -- v linear dimming range dim 0.3 -- 3.0 v led current off threshold voltage ioff th -- -- 0.3 v current source cs 290 300 310 a otp section o t p t rip point otp tp 140 150 160 o c o t p release point otp r p 1 20 130 140 o c otp threshold level otp t h -- 20 -- o c otp de - bounce time otp dbt 40 80 120 s note 1 : ocp, scp, otp: a uto r ecovery t ype note 2 : ovp , a uto r ecovery type (l atch off type optional)
ts 1970 2 high power factor corrector led driver 3 / 9 version: a12 function block pin description pin no. name function 1 v cc power s upply pin 2 gnd ground pin 3 out the output driver for driving the external mosfet 4 dim dimming control pin by input a dc voltage 5 comp feedback compensation network 6 cs current sense pin, connect to sense the mosfet current
ts 1970 2 high power factor corrector led driver 4 / 9 version: a12 application circuit application information start - up current the typical start - up current is around 8 a. very low start - up current allows the pwm controller to increase the value of start - up resistor and then reduce the power dissipation on it. uvlo (under voltage lockout) a hysteresis uvlo comparator is implemented in ts19702 , then the turn - on and turn - off thresholds level are fixed at 15v and 8v respectively. this hysteresis shown in fig.11 ensures that the start - up capacitor will be adequate to s upply the chip during start - up. for quickly startup the led driver, the start - up resistor should be matched with the startup capacitor. due to the low uvlo on level, so the turn - on delay time will also never greater than the general pwm ic. oscillator th e maximum duty - cycle of internal oscillator is up to 90 % for driving high led voltage string . the frequency of the oscillator is fix ed to 45khz by in ternal setting . leb (leading - edge blanking) each time the power mosfet is switch ed on, a turn - on spike wil l inevitably occur at the sense resistor. to avoid fault trigger, a 410 ns leading - edge blanking time is built in. conventional rc filtering can therefore be omitted. during this blanking period, the current - limit comparator is disabled and can not sw itch o ff the gate driver.
ts 1970 2 high power factor corrector led driver 5 / 9 version: a12 application information (continue) o c p (over current protection) the ts19702 has an over current protection function on cs pin . an internal circuit detects the current level, when the current is larger than a threshold level , the gate o utput will keep on low level. then v cc decreases below uvlo off level, the controller resets again. ovp (over voltage protection) on vcc to prevent the led driver from being damaged , t he ts19702 is implement e d an ovp function on vcc. when the vcc voltage i s higher than the ovp threshold voltage 28v , the output gate driver circuit will be shut down immediately to stop the sw itching of power mosfet. the v cc pin ovp function is a n auto recovery type protection (latch off type optional) . if the ovp condition ha ppen s , the pulses wi ll be stopped and never recover y unless the v cc pin voltage is down to the uvlo off level. the ts19702 i s working in a n auto - recovery mode as shown in below figure gate clamp/soft driving driver is clamped to 15v by an internal clampi ng circuit . those damages usually come from undesired over - voltage gate signals . under the conditions listed below, the gate output will turn off immediately to protect the power circuit . the ts19702 also has soft driving function to minimize emi. over tem perature protection/dimming function the typical application for dim pin is shown in above fig. the ntc thermistor is setting as an external otp protection. in the dim pin, there is one comparator for latch - off mode protection. while the voltage on this pin is lower than 0.3v, the ts19702 will shut down. when the voltage is in the range of 0.3 to 3.0v, the ts19702 is operating on the linear dimming range. while the voltage is higher than 3.0v, the ts19702 is operating on the normal status. it also could let this pin open when the function is not required for the user.
ts 1970 2 high power factor corrector led driver 6 / 9 version: a12 electrical characteristics curve figure 1 . star - up current vs. temperature figure 2 . operating current vs. temperature figure 3 . uvlo - off vs. temperature figure 4 . uvlo - on vs. t emperature figure 5. fb v ref vs. temperature figure 6. output sink current vs. temperature
ts 1970 2 high power factor corrector led driver 7 / 9 version: a12 electrical characteristics curve figure 7. output source current vs. temp. figure 8. input over voltage vs. temperature figure 9. open loop voltage vs . temperature figure 10. switching frequency vs. temp .
ts 1970 2 high power factor corrector led driver 8 / 9 version: a12 sot - 26 mechanical drawing unit: millimeters marking diagram rf = device code y = year code (2=2012 , 3=2013 , 4 =201 4 ..) m = month code for halogen free product ( o = jan, p =feb, q =mar, r =apl, s =may, t =jun, u =jul, v =aug, w =sep, x =oct, y =nov, z =dec) l = lot code
ts 1970 2 high power factor corrector led driver 9 / 9 version: a12 notice specifications of the products displayed herein are subject to change without notice . tsc or anyone on its behalf, assumes no responsibility or liability for any errors or inaccuracies. information contained herein is intended to provide a product description only. no license, express or implied, to any intellectual property rights is gr anted by this document. except as provided in tsc s terms and conditions of sale for such products, tsc assumes no liability whatsoever, and disclaims any express or implied warranty, relating to sale and/or use of tsc products including liability or warra nties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright, or other intellectual property right. the products shown herein are not designed for use in medical, life - saving, or life - sustaining application s. customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify tsc for any damages resulting from such improper use or sale.
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