UCC5646 Datasheet, PDF (1/7 Pages) Texas Instruments – 27-LINE 3-V - 5-V LVD TERMINATOR FOR WIDE ULTRA2, ULTRA3, ULTRA160 AND ULTRA320

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UCC5646, UCC5647
27-LINE 3ĆV - 5ĆV LVD TERMINATOR
FOR WIDE ULTRA2, ULTRA3, ULTRA160 AND ULTRA320
SLUS386B − FEBRUARY 2000 − REVISED APRIL 2001
D SCSI SPI-2, SPI-3, SPI-4,
Ultra160, Ultra320 Compliance
PM PACKAGE
(TOP VIEW)
D Smallest Footprint
D Lowest Channel
Capacitance, 2 pF
64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
L25− ₁
48 ^{DISCNCT1
D Less than 0.5-pF Capacitance
Differential Between Pairs
D 2.7 V to 5.25 V Operation
D Differential Failsafe Bias
L25+ ₂
L26− ₃
L26+ 4
L27− 5
L27+ 6
47 ^{DISCNCT2
46 L21−
45 L21+
44 L20−
43 L20+
D 64-Pin Low Profile QFP
STRMPWR 7
42 L19−
PTRMPWR 8
41 L19+
REG 9
40 DIFSENS
SGND 10
39 DIFFB
PGND 11
38 L18−
LVD 12
37 L18+
L10− 13
36 L17−
L10+ 14
35 L17+
L11− 15
34 L16−
L11+ 16
33 L16+
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
description
{For the UCC5647, Pin 47 is DISCNCT1 and Pin 48 is DISCNCT2.
The UCC5646 is a twenty-seven line active terminator for low-voltage-differential (LVD) SCSI networks. This
LVD SCSI-only design allows the user to reach peak bus performance, while reducing system cost. The device
is designed as an active Y-terminator to improve the frequency response of the LVD SCSI Bus. Designed with
a 2-pF (typical) channel capacitance, the UCC5646 allows for minimal bus loading for a maximum number of
peripherals. With the UCC5646, the designer is able to comply with the Ultra2, Ultra3, Ultra160 and Ultra320
specifications. The UCC5646 also provides a much-needed system migration path for the ever improving SCSI
system standards.
This device is available in the 64-pin low-profile QFP package for ease of layout use.
Single-ended (SE) and high-voltage differential (HVD) SCSI drivers are not supported.
AVAILABLE OPTIONS
DISCONNECT ^{PACKAGED DEVICESâ€} 
TA
STATUS
LOW PROFILE QFP
(PM)
0°C to 70°C
REGULAR
REVERSE
UCC5646PM
UCC5647PM
† _{The PM package is available taped and reeled. Add TR suffix to}
device type (e.g. UCC5646PMTR) to order quantities of 1000
devices per reel.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
Copyright  2001, Texas Instruments Incorporated
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