Datasheet

SN74LVT244B
3.3-V ABT OCTAL BUFFER/DRIVER
WITH 3-STATE OUTPUTS
SCAS354J − FEBRUARY 1994 − REVISED SEPTEMBER 2003
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
description/ordering information (continued)
To ensure the high-impedance state during power up or power down, 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.
This device is 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 device when it is 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.
terminal assignments
1234
A 1A1
1OE V
CC
2OE
B 1A2 2A4 2Y4 1Y1
C 1A3 2Y3 2A3 1Y2
D 1A4 2A2 2Y2 1Y3
E GND 2Y1 2A1 1Y4
FUNCTION TABLE
(each 4-bit buffer)
INPUTS
OUTPUT
OE A
OUTPUT
Y
L H H
L LL
H X Z
logic diagram (positive logic)
1
218
1Y1
1OE
1A1
416
1Y2
1A2
614
1Y3
1A3
812
1Y4
1A4
19
11 9
2Y1
2OE
2A1
13 7
2Y2
2A2
15 5
2Y3
2A3
17 3
2Y4
2A4
Pin numbers shown are for the DB, DW, NS, PW, and RGY packages.
GQN OR ZQN PACKAGE
(TOP VIEW)
1234
A
B
C
D
E