TS19720 taiwan semiconductor document number: ds_p0000210 1 version: b15 signal-stage pfc buck current control led driver description the TS19720 is a high power factor and high accurac y constant current pwm controller. it is able to cont rol total harmonic distortion (thd) and efficiency optimization by an external resistor. TS19720 achie ves high power factor and high efficiency by boundary conduction mode (bcm). the line and load regulation of led current are within 2.5%. TS19720 also provides gate driving voltage clamping, v cc over-voltage protection, and system output open/short circuit protection to increase ic performance. features low thd <15% constant current accuracy within 2.5% high power factor >0.9 low bom cost boundary conduction mode control gate output voltage clamp led open protection led short protection over current protection (ocp) over thermal protection (otp) application led lighting down light tube lamp par lamp bulb sot - 26 pin definition : 1. v cc 2. gnd 3. out 4. rt 5. com 6. cs notes: moisture sensitivity level: level 3. per j-std-020 typical application circuit
TS19720 taiwan semiconductor document number: ds_p0000210 2 version: b15 absolute maximum ratings (note 1) parameter symbol limit unit power supply pin v cc 40 v rt voltage to gnd v rt -0.3 to 5.5 v out voltage to gnd v out -0.3 to 40 v cs voltage to gnd v cs -0.3 to 5.5 v com voltage to gnd v com -0.3 to 5.5 v power dissipation @ t a =25 c p d 0.3 w esd rating (human body mode) (note 2) hbm 2 kv esd rating (machine mode) mm 200 v lead temperature (soldering 10 sec) t lead 260 c junction temperature range t j -40 to +150 c storage temperature range t stg -65 to +150 c thermal performance parameter symbol limit unit junction to case thermal resistance r ? jc 106.6 c/w junction to ambient thermal resistance r ? ja 220 c/w notes: r ? ja is the sum of the junction-to-case and case-to-amb ient thermal resistances. the case thermal referenc e is defined at the solder mounting surface of the drain pins. r ? ja is guaranteed by design while r ? ca is determined by the users board design. r ? ja shown below for single device operation on fr-4 pcb in still air. thermal resistance is specified with the component mounted on a low effective therm al conductivity test board in free air at t a =25 c. recommended operating conditions (note 3) parameter symbol conditions unit power supply pin v cc 33 v rt voltage to gnd v rt -0.3 to 5 v out voltage to gnd v out -0.3 to 19 v cs voltage to gnd v cs -0.3 to 5 v com voltage to gnd v com -0.3 to 5 v operating junction temperature range t j -40 to +125 c operating ambient temperature range t opa -40 to +85 c
TS19720 taiwan semiconductor document number: ds_p0000210 3 version: b15 electrical specifica tions (v cc = 18v, t a = 25c unless otherwise noted) parameter conditions symbol min typ max unit supply voltage start-up current v cc = v uvlo(on) -1v v cc(st) -- 45 -- a operating current with 1nf load on out pin i opa -- 2.1 2.6 ma uvlo(off) v uvlo(off) 7 8 9 v uvlo(on) v uvlo(on) 16 17.5 19 v ovp level on v cc pin v ovp 29 31 33 v voltage feedback feedback reference voltage v fb 0.196 0.2 0.204 v trans conductance g m -- 58 -- s output sink current i o-sink -- 5.8 -- a output source current i o-source -- 5.8 -- a current sensing cs limit voltage v ocp -- 1.4 -- v open loop voltage cs pin open v olp -- 5 -- v leading-edge blanking time leb t -- 400 -- ns delay to output -- 100 -- ns switching frequency start frequency f str 3 4.5 6 khz gate driver output rising time load capacitance =1nf t rise -- 90 -- ns falling time load capacitance =1nf t fall -- 40 -- ns vgate-clamp v gate -- 12.5 15 v thermal section thermal shutdown (note 4) -- 150 -- c thermal shutdown release (note 5) -- 120 -- c note: 1. stresses listed as the above absolute maximum rating s may cause permanent damage to the device. these are for stress ratings. functional operation of the device at thes e or any other conditions beyond those indicated in the operational sections of the specifications is not implied. exposure to absol ute maximum rating conditions for extended periods may remain possibility to affect device reliability. 2. devices are esd sensitive. handing precaution reco mmended.. 3. the device is not guaranteed to function outside its operating conditions. 4. guaranteed by design. 5. auto recovery type.
TS19720 taiwan semiconductor document number: ds_p0000210 4 version: b15 ordering information part no. package packing TS19720cx6 rfg sot-26 3,000pcs / 7 reel note: 1. compliant to rohs directive 2011/65/eu and in acco rdance to weee 2002/96/ec. 2. halogen-free according to iec 61249-2-21 definiti on. block diagram pin description pin no. name function 1 v cc power supply pin for all internal circuitry 2 gnd ground return for all internal circuitry 3 out gate driver output 4 rt efficiency / thd option pin 5 com output pin of error amplifier 6 cs input current sense pin
TS19720 taiwan semiconductor document number: ds_p0000210 5 version: b15 application information start-up current the typical start-up current is around 45 a. very low start-up current allows the pwm control ler to increase the value of start-up resistor and then reduce the powe r dissipation. under voltage lockout (uvlo) a hysteresis uvlo comparator is implemented in ts19 720. the turn-on and turn-off thresholds level are fixed at 17.5v and 8v respectively. this hysteresis shown in fig.3 ensures that the start-up capacitor will be adequate to supply the chip during start-up. for quick start-up of the led driver, the start-up resistor should be matched with the start-up capacitor. leading-edge blanking (leb) each time the power mosfet is switched on, a turn-o n spike will inevitably occur at the sense resistor . to avoid fault trigger, a 400ns leading-edge blanking time i s built in. conventional rc filtering can therefore be omitted. during this blanking period, the current-limit comp arator is disabled and cannot switch off the gate d river. gate clamp driver is clamped to 12.5v by an internal clamping circuit to avoid the gate of mosfet to get damaged. over current protection (ocp) the TS19720 has built-in cycle by cycle over curren t protection function on cs pin. as the cs pin volt age is larger than v ocp (1.4v), the gate output will be turned off immedia tely to avoid the driver board to be burned out. over voltage protection (ovp) on v cc to prevent the led driver from being damaged, the t s19720 has an implemented ovp function on v cc . when the v cc voltage is higher than the v ovp (31v), the output gate driver circuit will be shut down immediately to stop the switching of power mosfet. the v cc pin ovp function is an auto recovery type protecti on. if the ovp condition happens, the pulses will be stopped until the v cc pin voltage is down to the uvlo off level. the ts1 9720 is working in an auto-recovery mode as shown in fig. 4 . fig. 4 fig.3
TS19720 taiwan semiconductor document number: ds_p0000210 6 version: b15 package outline dimensions (unit: millimeters) sot-26 suggested pad layout (unit: millimeters) marking diagram sc = device code y = year code d = 2014 e = 2015 f = 2016 g = 2017 h = 2018 j = 2019 k = 2020 w = week code a ~ z = wk1~wk26 a ~ z = wk27~wk52 l = lot code a~z
TS19720 taiwan semiconductor document number: ds_p0000210 7 version: b15 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 erro rs or inaccuracies. information contained herein is intended to provide a product description only. no license, express or implied, to any intellectual property rights is granted by this document. except as provided in tscs terms and co nditions of sale for such products, tsc assumes no liability wh atsoever, and disclaims any express or implied warr anty, relating to sale and/or use of tsc products includi ng liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, cop yright, or other intellectual property right. the products shown herein are not designed for use in medical, life-saving, or life-sustaining applica tions. customers using or selling these products for use i n such applications do so at their own risk and agr ee to fully indemnify tsc for any damages resulting from such i mproper use or sale.
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