SN54GTL1655, SN74GTL1655
16-BIT LVTTL-TO-GTL/GTL+ UNIVERSAL BUS TRANSCEIVERS
WITH LIVE INSERTION
SCBS696E – JULY 1997 – REVISED NOVEMBER 1999
SN74GTL1655 . . . DGG PACKAGE
Members of the Texas Instruments
Widebus Family
(TOP VIEW)
UBT (Universal Bus Transceiver)
Combines D-Type Latches and D-Type
Flip-Flops for Operation in Transparent,
Latched, or Clocked Mode
1
64
63
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55
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1OEAB
1OEBA
CLK
1LEAB
1LEBA
2
3
V
CC
4
1A1
GND
1A2
1A3
GND
1A4
GND
1A5
GND
1A6
V
ERC
Translate Between GTL/GTL+ Signal Level
and LVTTL Logic Levels
5
GND
1B1
1B2
GND
1B3
1B4
1B5
GND
1B6
1B7
6
High-Drive (100 mA),
Low-Output-Impedance (12 Ω) Bus
Transceiver (B Port)
7
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Edge-Rate-Control Input Configures the
B-Port Output Rise and Fall Times
I
, Power-Up 3-State, and BIAS V
CC
off
Support Live Insertion
1A7
Bus Hold on Data Inputs Eliminates the
Need for External Pullup/Pulldown
Resistors on A Port
V
V
CC
CC
1A8
2A1
GND
2A2
2A3
GND
2A4
2A5
GND
2A6
GND
2A7
1B8
2B1
GND
2B2
2B3
GND
2B4
2B5
Distributed V
Minimizes High-Speed Switching Noise
and GND-Pin Configuration
CC
Package Options Include Thin Shrink
Small-Outline (DGG) and Ceramic Quad
Flat (HV) Packages
description
V
REF
2B6
GND
2B7
The ’GTL1655 devices are high-drive (100 mA),
low-output-impedance (12 Ω) 16-bit universal bus
transceivers (UBT) that provide LVTTL-to-
GTL/GTL+ and GTL/GTL+-to-LVTTL signal-level
translation. They are partitioned as two 8-bit
transceivers and combine D-type flip-flops and
D-type latches to allow for transparent, latched,
and clocked modes of data transfer similar to the
’16501 function. These devices provide an
interface between cards operating at LVTTL logic
levels and a backplane operating at GTL/GTL+
signal levels. Higher-speed operation is a direct
result of the reduced output swing (<1 V), reduced
input threshold levels and output edge control
(OEC ). The high drive is suitable for driving
double-terminated low-impedance backplanes
using incident-wave switching.
V
2B8
CC
2A8
GND
2OEAB
2OEBA
BIAS V
2LEAB
2LEBA
OE
CC
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.
Widebus, UBT, and OEC are trademarks of Texas Instruments Incorporated.
Copyright 1999, Texas Instruments Incorporated
UNLESS OTHERWISE NOTED this document contains PRODUCTION
DATA information 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.
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POST OFFICE BOX 655303 • DALLAS, TEXAS 75265