unisonic technologies co., ltd upsr100 preliminary cmos ic www.unisonic.com.tw 1 of 7 copyright ? 2015 unisonic technologies co., ltd qw-r502-946.d sop-8 high precision cc/cv primary side regulator ? description the utc upsr100 is a primary control unit for switch mode charger and adapter applications. the controlled variable is transferred by an auxiliary winding from the secondary to the primary side. the device uses pulse frequency modulation (pfm) method to build discontinuous conduction mode (dcm) flyback power supplies. the utc upsr100 operates in primary-side sensing and regulation. opto-coupler and t l431 could be eliminated. it also eliminates the need of loop compensation circuitry while maintaining stability. the utc upsr100 achieves high precision cv/cc regulation and high power efficiency. it offers comprehensive protection coverage with auto-recovery features including cycle-by-cycle current limiting, output over vo ltage protection, feedback loop open protection, short circuit protec tion, leading edge blanking, v cc under voltage lockout, etc. ? features * 5% constant voltage regulation at universal ac input * high precision constant current r egulation at universal ac input * primary side control without tl431 and opto-coupler * programmable cv and cc regulation * eliminates control loop compensation circuitry * flyback topology in dcm operation * random frequency modulation to reduce system emi * driver bjt switch * built-in leading edge blanking * built-in primary winding inductance compensation * open circuit protection * over voltage protection * short circuit protection ? ordering information ordering number package packing UPSR100G-S08-R sop-8 tape reel
upsr100 preliminary cmos ic unisonic technologies co., ltd 2 of 7 www.unisonic.com.tw qw-r502-946.d ? marking ? pin configuration ? pin description pin no. pin name description 1 cs current sense input. 2 v cc power supply. 3 out base drive for power bjt. 4 gnd ground. 5 fb the voltage feedback from the auxiliary winding 6 v dd the 5v output of the internal voltage regulator 7 bias this pin sets the bias current inside utc upsr100 with an external resistor to gnd 8 comp this pin connects a bypass capacitor ? block diagram 6 v dd 5v regulator & v ref por 2 v cc logic core ovp 8v + - 5 fb + - 4v cv controller ibias base drive i ref 7 bias + - 0.43v 3 out 1 + - 0.5v leb cc controller 8 comp 4 gnd tdemag detector cs
upsr100 preliminary cmos ic unisonic technologies co., ltd 3 of 7 www.unisonic.com.tw qw-r502-946.d
upsr100 preliminary cmos ic unisonic technologies co., ltd 4 of 7 www.unisonic.com.tw qw-r502-946.d ? absolute maximum rating parameter symbol ratings unit supply voltage v cc -0.3~30 v voltage at cs, bias, out, v dd , comp to gnd -0.3~7 v fb input (pin 5) -40~10 v esd (machine model) 200 v output current at out internally limited a power dissipation at t a =25c p d 0.657 w operating junction temperature t j 150 c storage temperature t stg -65~150 c note: absolute maximum ratings are those values be yond which the device could be permanently damaged. absolute maximum ratings are stress ratings only and functional device oper ation is not implied. ? thermal data description symbol ratings unit junction to ambient ja 190 c/w ? electrical characteristics (v cc =15v, t a =25c, unless otherwise specified.) parameter symbol test conditions min typ max unit uvlo section turn-on threshold voltage v th (on) 17.5 19 20.5 v turn-off threshold voltage v th(off) 6.5 7.5 8.5 v reference voltage section bias pin voltage v bias r bias =200k ? , before turn on 1.15 1.20 1.25 v vdd pin voltage v dd 4.75 5.0 5.25 v standby current section start-up current i st r bias =200k ? , before turn on 90 110 a operating current i op r bias =200k ? 500 700 a drive output section i out(sink) r bias =200k ? ,v out <0.2v 50 ma out maximum current i out(source) i out r bias =200k ? 30 40 ma current sense section current sense threshold v cs 505 520 545 mv pre-current sense v cs(pre) 455 480 505 mv leading edge blanking 460 ns feedback input section feedback pin input leakage current i fb v fb =4v 11.0 13.5 15.0 a feedback threshold v fb 3.90 4.00 4.10 v enable turn-on voltage v fb(en) -1.2 -1.0 -0.9 v comp threshold voltage section turn-on threshold voltage v comp 3.28 3.4 3.58 v protection section over voltage protection v fb(ovp) 7 8 9 v
upsr100 preliminary cmos ic unisonic technologies co., ltd 5 of 7 www.unisonic.com.tw qw-r502-946.d ? operation description the utc upsr100 is a primary control unit for switch mode charger and adapter applications. it operates in primary-side sensing and regulation. opto-coupler and tl43 1 could be eliminated. proprietary built-in cv and cc control can achieve high precision cv/cc performance. it uses pulse frequency modulation (pfm) method to build discontinuous conduction mode (dcm) flyback power supplies. startup control the voltage regulator provides the internal power supply v dd . for v cc and v dd external capacitors are required. the current biasing of utc upsr100 is adjustable by an external resistor. internal time constants, thresholds and the output current depend from the value of this resistor. the startup circui t activates the ic after startup and deactivates the ic in case of uvlo. operating current the operating current of utc upsr100 is as low as 500a. good efficiency and very low standby power can be achieved. constant voltage operation the output voltage is defined by the transmission ratio between the secondary and auxiliary winding. the utc upsr100 captures the auxiliary winding feedba ck voltage at fb pin and operates in constant-voltage (cv) mode to regulate the output voltage. the auxiliary voltage reflects the output voltage is given by: v ? + v n n = v o s a aux (1) where v indicates the drop voltag e of the output diode. figure 2. auxiliary voltage waveform via a resistor divider connected between the auxiliary winding and fb, the v aux is sampled at the tsampling end and it is hold until the next sampling. the sampled voltage is compared with 4v reference voltage and the error is amplified. the error amplifier output re flects the load condition and controls the toff time to regulate the output voltage, thus constant output voltage can be achieved. constant current operation when the sampled voltage is below 4v reference voltage a nd the error amplifier output reaches its maximum, thus utc upsr100 operates in constant-current ( cc) mode. the cc point and maximum output power can be externally adjusted by external current sense resistor rcs. the larg er rcs, the smaller cc point is, and the smaller output power becomes.
upsr100 preliminary cmos ic unisonic technologies co., ltd 6 of 7 www.unisonic.com.tw qw-r502-946.d ? operation description figure 3. adjustable output power by changing r cs figure 4. secondary current waveform in cc operation, the cc loop control function of utc upsr100 will keep a fixed proportion between secondary inductance de-magnetization time (tdemag) and switch ing cycle time (tsw). the fixed proportion is 7 4 = tsw tdemag (2) thus the output current is given by: ipk n n 7 2 = tsw tdemag ipk n n 2 1 = iout s p s p (3) current sensing and leading edge blanking cycle-by-cycle current limiting is offered in utc upsr100 . the switch current is detected by a sense resistor into the cs pin. when the power switch is turned on, a turn-on spike will occur on this resistor. a 500ns leading-edge blanking is built in to avoid false-termi nation of the switching puls e so that the external rc filtering is no longer needed. drive bjt the driver is a push pull stage with the supply voltage v cc . it provides the driving current for the external power bipolar transistor. the output signal is current-limited to i out(source) . protection control good power supply system reliability is achieved with its comprehensive protection features including output over-voltage protection, feedback loop open protection, cycl e-by-cycle current limiting, short circuit protection, leading edge blanking and uvlo, etc. v cc is supplied by transformer auxiliar y winding output. the output of utc upsr100 is shutdown when v cc drops below v th(off) and the power converter enters powe r on start-up sequence thereafter.
upsr100 preliminary cmos ic unisonic technologies co., ltd 7 of 7 www.unisonic.com.tw qw-r502-946.d ? typical application circuit l n vo is d1 co q1 rcs n a n p n s utc upsr100 bias gnd v dd v cc out cs fb comp io + + a typical flyback application by utc upsr100 utc assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all utc products described or contained herein. utc products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. the information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice.
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