Philips Semiconductors
Product specification
Quad 2-input multiplexer
FEATURES
•
5 V tolerant inputs for interfacing with 5 V logic
•
Wide supply voltage range from 1.2 to 3.6 V
•
CMOS low power consumption
•
Direct interface with TTL levels
•
Inputs accept voltages up to 5.5 V
•
Complies with JEDEC standard no. 8-1A
•
ESD protection:
HBM EIA/JESD22-A114-A exceeds 2000 V
MM EIA/JESD22-A115-A exceeds 200 V.
•
Specified from
−40
to +85
°C
and
−40
to +125
°C.
DESCRIPTION
The 74LVC157A is a high-performance, low-power,
low-voltage, Si-gate CMOS device and superior to most
advanced CMOS compatible TTL families.
74LVC157A
Inputs can be driven from either 3.3 or 5 V devices. This
feature allows the use of these devices as translators in a
mixed 3.3 and 5 V environment.
The 74LVC157A is a quad 2-input multiplexer which select
four bits of data from two sources under the control of a
common select input (S). The four outputs present the
selected data in the true (non-inverted) form. The enable
input (E) is active LOW. When pin E is HIGH, all of the
outputs (1Y to 4Y) are forced LOW regardless of all the
other input conditions. Moving the data from two groups of
registers to four common output buses is a common use of
the 74LVC157A. The state of the common data select
input (S) determines the particular register from which the
data comes. It can also be used as function generator.
The device is useful for implementing highly irregular logic
by generating any 4 of the 16 different functions of two
variables with one variable common.
The 74LVC157A is the logic implementation of a 4-pole,
2-position switch, where the position of the switch is
determined by the logic levels applied to pin S.
QUICK REFERENCE DATA
GND = 0 V; T
amb
= 25
°C;
t
r
= t
f
≤
2.5 ns.
SYMBOL
t
PHL
/t
PLH
PARAMETER
propagation delay
nI0, nI1 to nY
E to nY
S to nY
C
I
C
PD
Notes
1. C
PD
is used to determine the dynamic power dissipation (P
D
in
µW).
P
D
= C
PD
×
V
CC2
×
f
i
×
N +
Σ(C
L
×
V
CC2
×
f
o
) where:
f
i
= input frequency in MHz;
f
o
= output frequency in MHz;
C
L
= output load capacitance in pF;
V
CC
= supply voltage in Volts;
N = total load switching outputs;
Σ(C
L
×
V
CC2
×
f
o
) = sum of the outputs.
2. The condition is V
I
= GND to V
CC
.
input capacitance
power dissipation capacitance per gate
V
CC
= 3.3 V; notes 1 and 2
C
L
= 50 pF; V
CC
= 3.3 V
C
L
= 50 pF; V
CC
= 3.3 V
C
L
= 50 pF; V
CC
= 3.3 V
2.6
2.8
2.6
5.0
15
ns
ns
ns
pF
pF
CONDITIONS
TYPICAL
UNIT
2003 Dec 02
2
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