unisonic technologies co., ltd ur5517 linear integrated circuit www.unisonic.com.tw 1 of 9 copyright ? 2011 unisonic technologies co., ltd qw-r102-041.b 3a ddr bus termination regulator ? description the ur5517 is a linear regulator which provides up to 3 amp bi-directional sourcing and sinking capability for ddr1/2/3 sdram bus terminator applications. it only requires 20uf of ceramic output capacitance by a integrat ed operational amplifier which provides fast load transient response. the ur5517 also includes two control pins, s3 & s5. if s3 were set in low level, v tt will be turned off and left hi-z(sleep-state mode).if setting s5 were set in low level, both v tt and v ttref will be turned off and discharged to ground(soft-off mode). ? features * input voltage range:3~5.5v * v ldoin voltage range:1.2v~3.6v * ddr1/2/3 termination voltage applications * sourcing and sinking current up to 3a * 20mv accuracy for v tt and v ttref * 10ma buffered reference(v ttref ) * supports high-z in s3(str) and soft-off in s5(shutdown) * integrated divider tracks 1/2 v ddqsns for both v tt &v ttref * built-in soft-start * current limiting protection * thermal shutdown protection ? ordering information ordering number package packing lead free halogen free ur5517l-sm2-r ur5517g-sm2-r msop-10 tape reel ur5517l-sm2-t UR5517G-SM2-T msop-10 tube (1) r: tape reel, t: tube (2) sm2: msop-10 (3) g: halogen free, l: lead free ur5517l -sm2 -r (1)packing type (2)package type (3)lead free
ur5517 linear integrated circuit unisonic technologies co., ltd 2 of 9 www.unisonic.com.tw qw-r102-041.b pin configurations ? pin description (note) pin name pin type pin description v ddqsns i v ddq sense input v ldoin i power supply for the v tt & v ttref output stage v tt o output voltage for connection to termination resistors, equal to v ddqsns /2 pgnd o power ground output for the v tt output v ttsns i voltage sense input for the v tt . connect to plus terminal of the output capacitor v ttref o buffered output that is a reference output, equal to v ddqsns /2 s3 i active low suspend to ram mode control pin, v tt is turned off and left hi-z gnd i ground s5 i active low shutdown control pin, both v tt &v ttref are turned off and discharged to ground v in i analog input pin note recommend connecting the thermal pad to the gnd for the excellent power dissipation.
ur5517 linear integrated circuit unisonic technologies co., ltd 3 of 9 www.unisonic.com.tw qw-r102-041.b ? block diagram + + s3 s5 stb sd pgood current limit v ttref gnd pgnd v tt v ttsns v ldoin v in v ddqsns v ddqsns /2 v ddqsns / v ddqsns / *0.95 otp 2 1 *.05 2
ur5517 linear integrated circuit unisonic technologies co., ltd 4 of 9 www.unisonic.com.tw qw-r102-041.b ? absolute maximum rating (unless otherwise specified) parameter symbol ratings unit supply voltage(v in ,v ldoin ,v ddqsns ,s3,s5) -0.3~6 v power ground output for the v tt output p gnd -0.3~0.3 v output voltage(v tt ,v ttref ) v tt ,v ttref -0.3~v ldoin +0.3 v junction temperature t j 160 storage temperature t stg -55 ~ +160 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. ? recommended operating conditions (note1, 2) parameter symbol min typ max unit input voltage v in 3 5.5 v str and shutdown voltage s3,s5 -0.1 5.5 v v ddq sense input v ddqsns 1.3 3.6 v power supply for the v tt and v ttref output stage v ldoin 1.2 3.6 v power ground output for the v tt output p gnd -0.1 0.1 v operating temperature t a -40 85 note: 1. all voltage values are with respect to t he network ground terminal unless otherwise noted. 2. please always keep v ldoin ,v ttsns ,v ddqsns ,s3,s5 lower than v in on operation. ? electrical characteristics (v in =5v,v ldoin =v ddqsns =2.5v, t a =25 .unless otherwise specified) parameter symbol test conditions min typ max unit current of v in i vin s5=hi,s3=hi, no load(normal) 0.5 0.8 2 ma i vinstb s5=hi,s3=lo, no load(standby) 110 200 ua i vinsdn s5=lo,s3=lo, no load(shutdown) 1 ua current of v ldoin i vldoin s5=hi,s3=hi, no load(normal) 0.03 2 ma i vldoinstb s5=hi,s3=lo, no load(standby) 0.1 10 ua i vldoinsdn s5=lo,s3=lo, no load(shutdown) 0.1 1 ua input impedance of v ddqsns z vddqsns s5=hi,s3=hi 200 k ? input current of v ttsns i vttsns s5=hi,s3=hi 0.3 1 ua output voltage of v tt v tt ddr1(v ldoin =v ddqsns =2.5v) 1.25 v ddr2(v ldoin =v ddqsns =1.8v) 0.9 ddr3(v ldoin =v ddqsns =1.5v) 0.75 load regulation of v tt (v ttref -v tt ) vosv tt i vtt =0 -20 20 mv i O vtt < O 1.5a -30 30 i O vtt <3a O -40 40 source current limit of v tt i vttoclsrc v tt =v ddqsns /2*0.95,pgood=hi 3 4 a v tt =0 1.5 2 sink current limit of v tt i vttoclsnk v tt =v ddqsns /2*1.05,pgood=hi 3 4 a v tt =v ddqsns 1.5 2 leakage current of v tt i vttlk s5=hi,s3=lo 0.01 ua discharge current of v tt i vttdis s5=lo, v ddqsns =0v,v tt =0.5v 10 20 ma output voltage of v ttref v ttref ddr1(v ldoin =v ddqsns =2.5v) 1.25 v ddr2(v ldoin =v ddqsns =1.8v) 0.9 ddr3(v ldoin =v ddqsns =1.5v) 0.75 load regulation of v ttref v ttref i O vttref < O 10ma -20 20 mv high level input voltage v ih s3 & s5 pin 1.6 v low level input voltage v il s3 & s5 pin 1 logic input leakage current i ileak s3 & s5 pin -1 1 ua thermal shutdown temperature t sd v in =3v~5.5v 160 thermal shutdown hysteresis t sd v in =3v~5.5v 20
ur5517 linear integrated circuit unisonic technologies co., ltd 5 of 9 www.unisonic.com.tw qw-r102-041.b ? typical applications circuit v ddqsns v in v tt gnd v ldoin s5 pgnd s3 v ttsns v ttref 5v 2*10uf 10k 1.8v 10k c1 0.1uf c2 v3 v5 ddr2 vo1 rl1 io1 rl2 io2 rs5 rs3
ur5517 linear integrated circuit unisonic technologies co., ltd 6 of 9 www.unisonic.com.tw qw-r102-041.b ? typical characteristics
ur5517 linear integrated circuit unisonic technologies co., ltd 7 of 9 www.unisonic.com.tw qw-r102-041.b ? typical characteristics(cont.) output short circuit protection source 0 1 2 3 5 6 4 sink v in =5v, v ldoin =2.5v, v tt =1.25v v in =5v, v ldoin =2.5v, v tt =1.25v output short circuit protection output short current (a) 0 1 2 3 5 6 4 output short current (a) output short current (a) output short current (a) output short current (a) output short current (a)
ur5517 linear integrated circuit unisonic technologies co., ltd 8 of 9 www.unisonic.com.tw qw-r102-041.b ? typical characteristics(cont.) shutdown waveforms s3&s5 high to low i vtt =i vttref =0a vs5 vs3 v ttref v tt
ur5517 linear integrated circuit unisonic technologies co., ltd 9 of 9 www.unisonic.com.tw qw-r102-041.b 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.
|
