M54HC251

M74HC251

February 1993

8 BIT SIPO SHIFT REGISTER

B1R

(Plastic Package)

ORDER CODES :

M54HC251F1R

M74HC251M1R

M74HC251B1R

M74HC251C1R

F1R

(Ceramic Package)

M1R

(Micro Package)

C1R

(Chip Carrier)

PIN CONNECTIONS (top view)

NC =

No Internal

Connection

.

HIGH SPEED

.

LOW POWER DISSIPATION

.

HIGH NOISE IMMUNITY

.

OUTPUT DRIVE CAPABILITY

10 LSTTL LOADS

.

SYMMETRICAL OUTPUT IMPEDANCE

.

BALANCED PROPAGATION DELAYS

.

WIDE OPERATING VOLTAGE RANGE

.

PIN AND FUNCTION COMPATIBLE WITH

54/74LS251

DESCRIPTION

The M54/74HC251 is a high speed CMOS 8-CHAN-

NEL MULTIPLEXER (3-STATE) fabricated in silicon

gate C

speed performance of LSTTL combined with true

CMOS low power consumption. This multiplexer

features both true (Y) and complement (W) outputs

as well as STROBE input. The STROBE must be a

low logic level to enable this device. When the

STROBE input is high, both outputs are in the high

impedance state. When enabled, address informa-

tion on the data select inputs determines which data

input is routed to Y and W. All inputs are equipped

with protection circuits against static discharge and

transient excess voltage.

INPUT AND OUTPUT EQUIVALENT CIRCUIT

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