Datasheet
SN74GTL16622A
18-BIT LVTTL-TO-GTL/GTL+ BUS TRANSCEIVER
SCBS673F – AUGUST 1996 – REVISED AUGUST 2001
2–33
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
D Member of Texas Instruments’ Widebus
Family
D OEC Circuitry Improves Signal Integrity
and Reduces Electromagnetic Interference
D D-Type Flip-Flops With Qualified Storage
Enable
D Translates Between GTL/GTL+ Signal
Levels and LVTTL Logic Levels
D Supports Mixed-Mode (3.3 V and 5 V)
Signal Operation on A-Port and Control
Inputs
D I
off
Supports Partial-Power-Down Mode
Operation
D Bus Hold on Data Inputs Eliminates the
Need for External Pullup/Pulldown
Resistors on A Port
D Distributed V
CC
and GND Pins Minimize
High-Speed Noise
D Latch-Up Performance Exceeds 250 mA Per
JESD 17
D ESD Protection Exceeds JESD 22
– 2000-V Human-Body Model (A114-A)
– 200-V Machine Model (A115-A)
– 1000-V Charged-Device Model (C101)
description
The SN74GTL16622A is an 18-bit registered bus
transceiver that provides LVTTL-to-GTL/GTL+
and GTL/GTL+-to-LVTTL signal-level translation.
This device is partitioned as two separate 9-bit
transceivers with individual clock-enable controls
and contains D-type flip-flops for temporary
storage of data flowing in either direction. This
device provides 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 OEC circuitry.
The user has the flexibility of using this device at either GTL (V
TT
= 1.2 V and V
REF
= 0.8 V) or the preferred
higher noise margin GTL+ (V
TT
= 1.5 V and V
REF
= 1 V) signal levels. GTL+ is the Texas Instruments derivative
of the Gunning Transceiver Logic (GTL) JEDEC standard JESD 8-3. The B port normally operates at GTL or
GTL+ signal levels, while the A-port and control inputs are compatible with LVTTL logic levels and are 5-V
tolerant. V
REF
is the reference input voltage for the B port.
Copyright 2001, Texas Instruments Incorporated
OEC and Widebus are trademarks of Texas Instruments.
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OEAB
1A1
GND
1A2
1A3
GND
V
CC
1A4
GND
1A5
1A6
GND
1A7
1A8
GND
1A9
2A1
GND
2A2
2A3
GND
2A4
2A5
GND
2A6
V
CC
GND
2A7
2A8
GND
2A9
OEBA
CLKAB
1CEAB
1CEBA
1B1
GND
1B2
1B3
V
CC
1B4
1B5
1B6
GND
1B7
1B8
GND
1B9
2B1
GND
2B2
2B3
GND
2B4
2B5
2B6
V
REF
2B7
2B8
GND
2B9
2CEBA
2CEAB
CLKBA
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.