lin d oc #: 5120 ultra 27-l ine scsi t erminator p roduction d ata s heet t he i nfinite p ower of i nnovation lx5120 description key features ultra-fast response for fast-20 scsi applications split disconnect for mixing 16-bit (wide) or 8-bit (narrow) buses 35mhz channel bandwidth sleep-mode current less than 150a hot-swap compatible no external compensation capacitors compatible with active negation drivers superior pin-for-pin replacement for the ucc5620 0 to 125 LX5120CDB package order info t j (c) receiver lx5120 lx5120 lx5268 lx5268 1 meter, awg 28 driver d riving w aveform - 20mh z r eceiving w aveform - 20mh z product highlight the lx5120 ultramax tm terminator represents next-generation technology for scsi termina- tion applications. the low-voltage bicmos architecture employed in its design offers superior performance to older passive and active techniques. linfinity's architecture employs high-speed adaptive elements for each channel, providing the fastest response possible. the channel bandwidth is typically 35mhz. the lx5120 compares favorably to older linear regulator approaches whose bandwidth's are domi- nated by the output compensation capacitor and are limited to the 500khz bandwidth region (see further discussion in the func- tional description section). linfinity's archi- tecture also eliminates the output compen- sation capacitor typical in earlier terminator designs. each is approved for use with scsi- 1,-2,-3, ultra and beyond ? providing the highest performance alternative available to- day. another key improvement of lx5120 prod- ucts lies in their ability to ensure reliable, error- free communications even in systems which do not necessarily adhere to recommended scsi hardware design guidelines, such as the use of improper cable lengths and imped- ances. frequently, this situation is not con- trolled by the peripheral or host designer and, when problems occur, they are the first to be made aware of these problems. the lx5120 architecture is much more tolerant of marginal system integrations. recognizing the needs of portable and configurable peripherals, the lx5120 has a ttl compatible sleep/disable mode. to enter this mode, the dis pin must be driven low, thereby disconnecting the lx5120 from the scsi bus. quiescent current is less than 150a in this mode. reduced component count is also inherent in the lx5120 architecture. traditional ter- mination techniques require large stabiliza- tion and transient protection capacitors of up to 20f in value and size. the lx5120 architecture does not require these compo- nents, allowing all the cost savings associated with inventory, board space, assembly, re- liability, and component costs. note: for an in-depth discussion on applying scsi, request linfinity application note: "understanding the single-ended scsi bus" ultramax tm note: available in tape & reel. append the letter "t" to part number. (i.e. LX5120CDBt) plastic ssop 36-pin db copyright ? 2000 rev. 1.0 4/00 1 11861 w estern a venue , g arden g rove , ca. 92841, 714-898-8121, f ax : 714-893-2570 l in f inity m icroelectronics i nc . note: for current data & package dimensions, visit our web site: http://www.linfinity.com.
ultra 27-l ine , p lug and p lay scsi t erminator lx5120 product databook 1996/1997 copyright ? 2000 rev. 1.0 4/00 2 p roduction d ata s heet ultramax 2.65 2.85 v 12 20 ma 635 670 ma 10 150 a -20 -23 -24 ma -10 a 1a 35 mhz 7ma termination voltage v term high level disable input voltage v ih low level disable input voltage v il operating virtual junction temperature range lx5120c recommended operating conditions (note 2) parameter symbol units recommended operating conditions min. typ. max. 4.0 5.5 v 2v term v 00.8v 0 125 c note 2. range over which the device is functional. electrical characteristics term power = 4.75v unless otherwise specified. unless otherwise specified, these specifications apply at the recommended operating ambient tempera- ture of t a = 25c. low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature. parameter symbol test conditions units lx5120 min. typ. max. output high voltage v out termpwr supply current i cc all data lines = open all data lines = 0.2v dis (disable) pin >2.0v output current i out v out = 0.2v disable input current i in dis = 0v output leakage current dis > 2.0v, v o = 0.2v channel bandwidth bw termination sink current, per channel i sink v out = 4v absolute maximum ratings (note 1) termpwr voltage ..................................................................................................... 7v continuous output voltage range .............................................................. 0 to 5.5v continuous disable voltage range .............................................................. 0 to 5.5v operating junction temperature plastic (db package) ..................................................................................... 150oc storage temperature range ............................................................. -65c to +150c solder temperature (soldering, 10 seconds) ................................................... 300c note 1. exceeding these ratings could cause damage to the device. package pin outs db package: thermal resistance-junction to ambient, ja 50c/w junction temperature calculation: t j = t a + (p d x ja ). the ja numbers are guidelines for the thermal performance of the device/pc-board system. all of the above assume no ambient airflow. thermal data db package (top view) t27 t26 t25 t18 t17 t16 t15 n.c. gnd gnd gnd v t t14 t13 t12 t11 t24 t23 t19 t20 t1 t2 t3 t4 t5 gnd gnd gnd dis t6 t7 t8 t9 t10 t21 t22 136 235 334 433 532 631 730 829 928 10 27 11 26 12 25 13 24 14 23 15 22 16 21 17 20 18 19
ultra 27-l ine , p lug and p lay scsi t erminator lx5120 product databook 1996/1997 3 copyright ? 2000 rev. 1.0 4/00 p roduction d ata s heet ultramax block diagram functional description term power current biasing circuit 1.4v dis 24ma current limiting circuit data output pin db(0) 2.85v 1 of 27 channels cable transmission theory suggests that in order to optimize signal speed and quality, the termination should act both as an ideal voltage reference when the line is released (de-asserted) and as an ideal current source when the line is active (asserted). common active terminators, which consist of linear regulators in series with resis- tors (typically 110 ? ), are a compro- mise. as the line voltage increases, the amount of current decreases lin- early by the equation v = i * r. the ultramax lx5120, with its unique new architecture, applies the maximum amount of current regardless of line voltage until the termination high threshold (2.85v) is reached. acting as a near ideal line terminator, the lx5120 closely disable outputs quiescent lx5120 current l enabled 20ma (max.) h hi z 150a (max.) open hi z 150a (max.) p ower u p / p ower d own f unction t able reproduces the optimum case when the device is enabled. to enable the device the dis (disable) pin should be driven low. during this mode of operation, quiescent current is 20ma (max.) and the device will respond to line demands by delivering 24ma on assertion and by imposing 2.85v on de- assertion. disable mode places the device in a sleep state, where a meager 150a (max.) of quiescent current is consumed. additionally, all outputs are in a hi-z (impedance) state. sleep mode can be used for power conser- vation or to completely eliminate the terminator from the scsi chain. an additional feature of the lx5120 is its compatibility with active negation drivers. ultramax is a trademark of linfinity microelectronics inc. production data - information contained in this document is proprietary to linfinity, and is current as of publication date. t his document may not be modified in any way without the express written consent of linfinity. pro duct processing does not necessarily include testing of all parameters. linfinity reserves the right to change the configuration and performance of the product and to discontinue pro duct at any time.
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