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QUAD 2-INPUT MULTIPLEXER
Fast CMOS
Quad 2-Input Multiplexer
Product Features:
聲 PI74FCT157/257/2157/2257T is pin compatible with bipolar
FAST聶 Series at a higher speed and lower power
consumption
聲 25鈩?series resistor on all outputs (FCT2XXX only)
聲 TTL input and output levels
聲 Low ground bounce outputs (25鈩?series only)
聲 Extremely low static power
聲 Hysteresis on all inputs
聲 Industrial operating temperature range: 聳40擄C to +85擄C
聲 Packages available:
聳 16-pin 150 mil wide plastic QSOP (Q)
聳 16-pin 300 mil wide plastic SOIC (S)
聳 16-pin 150 mil wide plastic SOIC (W)
Product Description:
Pericom Semiconductor聮s PI74FCT series of logic circuits are pro-
duced in the Company聮s advanced 0.8 micron CMOS technology,
achieving industry leading speed grades. All PI74FCT2XXX devices
have a built-in 25-ohm series resistor on all outputs to reduce noise
because of reflections, thus eliminating the need for an external
terminating resistor.
The PI74FCT157T/257T and PI74FCT2157T/2257T are high-
speed quad 2-input multiplexers. The common select input can be
used to select four bits of data from two sources. The four buffered
outputs present the selected data in the true (non-inverting) form.
The PI74FCT157T/2157T has a common, active-LOW, Enable
input (E). When E is inactive, all four outputs are held LOW. The
PI74FCT157T/2157T can generate any four of the 16 different
funtions of two variables with one common variable. The
PI74FCT157T/2157T can be used as a function generator or to
move data from two different groups of registers to a common bus.
The PI74FCT257/2257T has a common Output Enable (OE) input.
When OE is HIGH, all outputs are switched to a high-impedance
state allowing the outputs to interface directly with bus-oriented
systems.
Logic Block Diagram
S
157
ONLY
E
3 OTHER MULTIPLEXERS
I
1
B-I
1
D
Z
B
-Z
D
I
0
B-I
0
D
I
1
A
Z
A
I
0
A
257
ONLY
OE
1
PS2010A 03/09/96
1
2
3
4
5
