SN54ALVTH32373, SN74ALVTH32373
2.5-V/3.3-V 32-BIT TRANSPARENT D-TYPE LATCHES
WITH 3-STATE OUTPUTS
SCES322A – FEBRUARY 2000 – REVISED APRIL 2000
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
D
State-of-the-Art Advanced BiCMOS
Technology (ABT) Widebus+ Design for
2.5-V and 3.3-V Operation and Low
Static-Power Dissipation
D
Support Mixed-Mode Signal Operation (5-V
Input and Output Voltages With 2.3-V to
3.6-V V
CC
)
D
Typical V
OLP
(Output Ground Bounce)
<0.8 V at V
CC
= 3.3 V, T
A
= 25°C
D
High Drive (–24/24 mA at 2.5-V and
–32/64 mA at 3.3-V V
CC
)
D
I
off
and Power-Up 3-State Support Hot
Insertion
D
Use Bus Hold on Data Inputs in Place of
External Pullup/Pulldown Resistors to
Prevent the Bus From Floating
NOTE: For tape and reel order entry:
The GKER package is abbreviated to KR.
D
Auto3-State Eliminates Bus Current
Loading When Output Exceeds V
CC
+ 0.5 V
D
Flow-Through Architecture Facilitates
Printed Circuit Board Layout
D
Distributed V
CC
and GND Pins Minimize
High-Speed Switching Noise
D
Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
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)
D
Packaged in Plastic Fine-Pitch Ball Grid
Array Package
description
The ’ALVTH32373 devices are 32-bit transparent D-type latches with 3-state outputs designed for 2.5-V or 3.3-V
V
CC
operation, but with the capability to provide a TTL interface to a 5-V system environment. These devices
are particularly suitable for implementing buffer registers, I/O ports, bidirectional bus drivers, and working
registers.
These devices can be used as four 8-bit latches, two 16-bit latches, or one 32-bit latch. When the latch-enable
(LE) input is high, the Q outputs follow the data (D) inputs. When LE is taken low, the Q outputs are latched at
the levels set up at the D inputs.
A buffered output-enable (OE
) input can be used to place the eight outputs in either a normal logic state (high
or low logic levels) or the high-impedance state. In the high-impedance state, the outputs neither load nor drive
the bus lines significantly. The high-impedance state and increased drive provide the capability to drive bus lines
without interface or pullup components.
OE
does not affect internal operations of the latch. Old data can be retained or new data can be entered while
the outputs are in the high-impedance state.
Inputs can be driven from either 3.3-V or 5-V devices. This feature allows the use of these devices as translators
in a mixed 3.3-V/5-V system environment.
These devices are fully specified for hot-insertion applications using I
off
and power-up 3-state. The I
off
circuitry
disables the outputs, preventing damaging current backflow through the devices when they are powered down.
The power-up 3-state circuitry places the outputs in the high-impedance state during power up and power down,
which prevents driver conflict.
When V
CC
is between 0 and 1.2 V, the devices are in the high-impedance state during power up or power down.
However, to ensure the high-impedance state above 1.2 V, OE
should be tied to V
CC
through a pullup resistor;
the minimum value of the resistor is determined by the current-sinking capability of the driver.
Copyright 2000, Texas Instruments Incorporated
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+ is a trademark of Texas Instruments.
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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