74ACT257
QUAD 2 CHANNEL MULTIPLEXER (3-STATE)
April 1997
n HIGH SPEED: t
PD
=5 ns (TYP.) at V
CC
=5V
n LOW POWER DISSIPATION:
I
CC
=8µA (MAX.) at T
A
=25
o
C
n COMPATIBLE WITH TTL OUTPUTS
V
IH
=2V(MIN),V
IL
= 0.8V (MAX)
n 50Ω TRANSMISSION LINE DRIVING
CAPABILITY
n SYMMETRICAL OUTPUT IMPEDANCE:
|IOH|=IOL =24mA(MIN)
n BALANCED PROPAGATION DELAYS:
t
PLH
≅ t
PHL
n OPERATING VOLTAGE RANGE:
VCC (OPR) = 4.5V to 5.5V
n PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 257
n IMPROVED LATCH-UP IMMUNITY
DESCRIPTION
The ACT257 is an advanced high-speed CMOS
QUAD 2 CHANNEL MULTIPLEXER (3-STATE)
fabricated with sub-micron silicon gate and
double-layer metal wiring C
2
MOS technology.
It is ideal for low power applications mantaining
high speed operation similar to equivalent Bipolar
Schottky TTL.
These IC’s are composed of an independent 2
channel multiplexer with common SELECT and
ENABLE INPUT.
The AC257 is a non inverting multiplexer.
When the ENABLE INPUT is held ”High” outputs
of both IC’s become high impedance state. If
SELECT INPUT is held ”Low”, ”A” data is
selected, when SELECT INPUT is ”High”, ”B”
data is closen.
The device is designed to interface directly High
Speed CMOS systems with TTL, NMOS and
CMOS output voltage levels.
All inputs and outputs are equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
voltage.
PIN CONNECTION AND IEC LOGIC SYMBOLS
ORDER CODES :
74ACT257B 74ACT257M
M
(Micro Package)
B
(Plastic Package)
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