unisonic technologies co., ltd ur5517 preliminary linear integrated circuit www.unisonic.com.tw 1 of 6 copyright ? 2010 unisonic technologies co., ltd qw-r102-041.a 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 integrated operati onal amplifier which provides fast load transient response. the ur5517 also includes two control pins, s3 & s5. if s3 were set in low level, vtt will be turned off and left hi-z(sleep-state mode).if setting s5 were set in low level, both vtt and vttref will be turned off and discharged to ground(soft-off mode). ? features * input voltage range::3~5.5v * vldoin voltage range:1.2v~3.6v * ddr1/2/3 termination voltage applications * sourcing and sinking current up to 3a * 20mv accuracy for vtt and vttref * 10ma buffered reference(vttref) * supports high-z in s3(str) and soft-off in s5(shutdown) * integrated divider tracks 1/2 vddqsns for both vtt&vttref * built-in soft-start * current limiting protection * thermal shutdown protection msop-10 ? ordering information ordering number package packing UR5517G-SM2-R msop-10 tape reel (1) r: tape reel (2) sm2: msop-10 (3) g: halogen free ur5517g -sm2 -r (1)packing type (2)package type (3)halogen free
ur5517 preliminary linear integrated circuit unisonic technologies co., ltd 2 of 6 www.unisonic.com.tw qw-r102-041.a ? pin configurations ? pin description (note) pin name pin type pin description vddqsns i vddq sense input vldoin i power supply for the vtt & vttref output stage vtt o output voltage for connection to te rmination resistors, equal to vddqsns/2 pgnd o power ground output for the vtt output vttsns i voltage sense input for the vtt. c onnect to plus terminal of the output capacitor vttref o buffered output that is a reference output, equal to vddqsns/2 s3 i active low suspend to ram mode control pin, vtt is turned off and left hi-z gnd i ground s5 i active low shutdown control pin, both vt t&vttref are turned off and discharged to ground vin i analog input pin note recommend connecting the thermal pad to the gnd for the excellent power dissipation.
ur5517 preliminary linear integrated circuit unisonic technologies co., ltd 3 of 6 www.unisonic.com.tw qw-r102-041.a ? block diagram + + s3 s5 stb sd pgood current limit vttref gnd pgnd vtt vttsns vldoin vin vddqsns vddqsns /2 vddqsns / vddqsns/ *0.95 otp 2 1 *.05 2
ur5517 preliminary linear integrated circuit unisonic technologies co., ltd 4 of 6 www.unisonic.com.tw qw-r102-041.a ? absolute maximum rating (unless otherwise specified) parameter symbol ratings unit supply voltage(vin,vldoin,v ddqsns,s3,s5) -0.3~6 v power ground output for the vtt output p gnd -0.3~0.3 v output voltage(vtt,vttref) vtt,v ttref -0.3~vldoin+0.3 v junction temperature t j 160 storage temperature t stg -55 ~ +160 note: absolute maximum ratings are those values beyo nd 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 vddq sense input v ddqsns 1.3 3.6 v power supply for the vtt and vttref output stage v ldoin 1.2 3.6 v power ground output for the vtt output p gnd -0.1 0.1 v operating temperature t a -40 85 1. all voltage values are with respect to t he network ground terminal unless otherwise noted. note: 2. please always keep vldoin,vttsns,vddqsn s,s3,s5 lower than vin on operation. ? electrical characteristics (v in =5v,vldoin=vddqsns=2.5v, t a =25 .unless otherwise specified) parameter symbol test conditions min typ max unit 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 current of vin i vinsdn s5=lo,s3=lo, no load(shutdown) 1 ua 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 current of vldoin i vldoinsdn s5=lo,s3=lo, no load(shutdown) 0.1 1 ua input impedance of vddqsns z vddqsns s5=hi,s3=hi 200 k ? input current of vttsns i vttsns s5=hi,s3=hi 0.3 1 ua ddr1(vldoin=vddqsns=2.5v) 1.25 ddr2(vldoin=vddqsns=1.8v) 0.9 output voltage of vtt vtt ddr3(vldoin=vddqsns=1.5v) 0.75 v i vtt =0 -20 20 O i vtt < O 1.5a -30 30 load regulation of vtt (vttref-vtt) vosvtt O i vtt <3a O -40 40 mv vtt=vddqsns/2*0.95,pgood=hi 3 4 source current limit of vtt i vttoclsrc vtt=0 1.5 2 a vtt=vddqsns/2*1.05,pgood=hi 3 4 sink current limit of vtt i vttoclsnk vtt=vddqsns 1.5 2 a leakage current of vtt i vttlk s5=hi,s3=lo 0.01 ua discharge current of vtt i vttdis s5=lo, vddqsns=0v,vtt=0.5v 10 20 ma ddr1(vldoin=vddqsns=2.5v) 1.25 ddr2(vldoin=vddqsns=1.8v) 0.9 output voltage of vttref v ttref ddr3(vldoin=vddqsns=1.5v) 0.75 v load regulation of vttref v ttref O i vttref < O 10ma -20 20 mv high level input voltage v ih s3 & s5 pin 1.6 low level input voltage v il s3 & s5 pin 1 v logic input leakage current i ileak s3 & s5 pin -1 1 ua thermal shutdown temperature t sd vin=3v~5.5v 160 thermal shutdown hysteresis t sd vin=3v~5.5v 20
ur5517 preliminary linear integrated circuit unisonic technologies co., ltd 5 of 6 www.unisonic.com.tw qw-r102-041.a ? typical applications circuit vddqsns vin vtt gnd vldoin s5 pgnd s3 vttsns vttref 5v 2*10uf 10k 2.5v 10k c1 0.1uf c2 v3 v5 ddr1 vo1 rl1 io1 rl2 io2 rs5 rs3 vddqsns vin vtt gnd vldoin s5 pgnd s3 vttsns vttref 5v 2*10uf 10k 1.8v 10k c1 0.1uf c2 v3 v5 ddr2 vo1 rl1 io1 rl2 io2 rs5 rs3
ur5517 preliminary linear integrated circuit unisonic technologies co., ltd 6 of 6 www.unisonic.com.tw qw-r102-041.a 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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