– Low input and output leakage ≤1µA (max.)
– CMOS power levels
– True TTL input and output compatibility
– VOH = 3.3V (typ.)
– VOL = 0.3V (typ.)
– Meets or exceeds JEDEC standard 18 specifications
– Product available in Radiation Tolerant and Radiation
Enhanced versions
– Military product compliant to MIL-STD-883, Class B
and DESC listed (dual marked)
– Available in DIP, SOIC, SSOP, QSOP, CERPACK
and LCC packages
• Features for FCT157T/257T:
– Std., A, C and D speed grades
– High drive outputs (-15mA IOH, 48mA IOL)
• Features for FCT2257T:
– Std., A, and C speed grades
– Resistor outputs(-15mA I
(-12mA IOH, 12mA IOL Mil.)
– Reduced system switching noise
OH, 12mA IOL Com.)
IDT54/74FCT157T/AT/CT/DT
IDT54/74FCT257T/AT/CT/DT
IDT54/74FCT2257T/AT/CT
DESCRIPTION:
The FCT157T, FCT257T/FCT2257T are high-speed quad
2-input multiplexers built using an advanced dual metal CMOS
technology. Four bits of data from two sources can be
selected using the common select input. The four buffered
outputs present the selected data in the true (non-inverting)
form.
The FCT157T has a common, active-LOW, enable input.
When the enable input is not active, all four outputs are held
LOW. A common application of ‘FCT157T is to move data
from two different groups of registers to a common bus.
Another application is as a function generator. The ‘FCT157T
can generate any four of the 16 different functions of two
variables with one variable common.
The FCT257T/FCT2257T have 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.
The FCT2257T has balanced output drive with current
limiting resistors. This offers low ground bounce, minimal
undershoot and controlled output fall times-reducing the need
for external series terminating resistors. FCT2xxxT parts are
plug-in replacements for FCTxxxT parts.
FUNCTIONAL BLOCK DIAGRAM
S
157 Only
1B–I1D
I
I0B–I
E
3 other multiplexers
0D
1A
I
0A
I
OE257 Only
Z B–Z D
A
Z
2537 drw 01
PIN CONFIGURATIONS
1
S
I
I
GND
2
0A
1A
Z
A
I
0B
I
1B
B
Z
3
4
5
6
7
8
P16-1,
D16-1,
SO16-1,
SO16-7
E16-1
DIP/SOIC/QSOP/CERPACK
TOP VIEW
INDEX
1A
I
ZA
NCNC
I0B
I1B
0A
I
32
4
5
6
7
8
10 11 12 13
9
ZB
LCC
&
NC
S
1
L20-2
NC
GND
Vcc
20 19
ZDI
16
15
14
13
12
11
10
9
E or OE*
18
17
16
15
14
1D
Vcc
E or OE*
I
0C
I
1C
Z
C
I
0D
I
1D
D
Z
I0C
I
1C
ZC
I
0D
2537 drw 02
2537 drw 03
TOP VIEW
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
* E for FCT157, OE for FCT257/FCT2257.
MILITARY AND COMMERCIAL TEMPERATURE RANGESJUNE 1996
1996 Integrated Device Technology, Inc. 6.6 2537/6
1
IDT54/74FCT157T/AT/CT/DT, IDT54/74FCT257T/AT/CT/DT- 2257T/AT/CT
FAST CMOS QUAD 2-INPUT MULTIPLEXERMILITARY AND COMMERCIAL TEMPERATURE RANGES
PIN DESCRIPTION
Pin NamesDescription
0A–I0DSource 0 Data Inputs
I
1A–I1DSource 1 Data Inputs
I
EOE
SSelect Input
A–ZDOutputs
Z
ABSOLUTE MAXIMUM RATINGS
SymbolRatingCommercialMilitaryUnit
(2)
VTERM
(3)
VTERM
TAOperating
TBIASTemperature
TSTGStorage
PTPower Dissipation0.50.5W
IOUTDC Output
NOTES:
1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating
only and functional operation of the device at these or any other conditions
above those indicated in the operational sections of this specification is
not implied. Exposure to absolute maximum rating conditions for
extended periods may affect reliability. No terminal voltage may exceed
V