Integrated Device Technology, Inc.
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.
FAST CMOS
QUAD 2-INPUT
MULTIPLEXER
IDT54/74FCT157T/AT/CT/DT
IDT54/74FCT257T/AT/CT/DT
IDT54/74FCT2257T/AT/CT
MILITARY AND COMMERCIAL TEMPERATURE RANGES
JUNE 1996
1
1996 Integrated Device Technology, Inc.
6.6
2537/6
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
FEATURES:
Common features:
Low input and output leakage
1
A (max.)
CMOS power levels
True TTL input and output compatibility
V
OH
= 3.3V (typ.)
V
OL
= 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 I
OH
, 48mA I
OL
)
Features for FCT2257T:
Std., A, and C speed grades
Resistor outputs
(-15mA I
OH
, 12mA I
OL
Com.)
(-12mA I
OH
, 12mA I
OL
Mil.)
Reduced system switching noise
E
157 Only
3 other multiplexers
OE
257 Only
Z
A
Z
B
Z
D
S
I
1B
I
1D
I
0B
I
0D
I
1A
I
0A
2537 drw 01
2537 drw 02
2537 drw 03
FUNCTIONAL BLOCK DIAGRAM
PIN CONFIGURATIONS
LCC
TOP VIEW
4
5
6
7
8
L20-2
18
17
16
15
14
9 10 11 12 13
3
2
1
20 19
INDEX
GND
NC
Vcc
E or OE*
NC
NC
NC
S
I
0A
I
1A
Z
A
I
0B
I
1B
Z
B
Z
D
I
1D
I
0C
I
1C
Z
C
I
0D
DIP/SOIC/QSOP/CERPACK
TOP VIEW
5
6
7
8
S
I
0A
1
2
3
4
16
15
14
13
12
11
10
9
Vcc
P16-1,
D16-1,
SO16-1,
SO16-7
&
E16-1
I
1A
Z
A
I
0B
I
1B
GND
Z
E or OE*
I
0C
I
1C
Z
C
I
0D
I
Z
D
B
1D
*
E
for FCT157,
OE
for FCT257/FCT2257.
6.6
2
IDT54/74FCT157T/AT/CT/DT, IDT54/74FCT257T/AT/CT/DT- 2257T/AT/CT
FAST CMOS QUAD 2-INPUT MULTIPLEXER
MILITARY AND COMMERCIAL TEMPERATURE RANGES
PIN DESCRIPTION
Pin Names
Description
I
0A
I
0D
Source 0 Data Inputs
I
1A
I
1D
Source 1 Data Inputs
E
Enable Input (Active LOW)FCT157T
OE
Output Enable (Active LOW)FCT257T/2257T
S
Select Input
Z
A
Z
D
Outputs
2537 tbl 01
FUNCTION TABLE
(1)
Inputs
Output Z
N
E
E
/
OE
OE
S
I
0
I
1
157
257
H
X
X
X
L
Z
L
H
X
L
L
L
L
H
X
H
H
H
L
L
L
X
L
L
L
L
H
X
H
H
NOTE:
2537 tbl 02
1. H = HIGH Voltage Level
L = LOW Voltage Level
X = Don't Care
Z = High Impedance
ABSOLUTE MAXIMUM RATINGS
(1)
CAPACITANCE
(T
A
= +25
C, f = 1.0MHz)
Symbol
Rating
Commercial
Military
Unit
V
TERM(2)
Terminal Voltage
with Respect to
GND
0.5 to +7.0
0.5 to +7.0
V
V
TERM(3)
Terminal Voltage
with Respect to
GND
0.5 to
V
CC
+0.5
0.5 to
V
CC
+0.5
V
T
A
Operating
Temperature
0 to +70
55 to +125
C
T
BIAS
Temperature
Under Bias
55 to +125
65 to +135
C
T
STG
Storage
Temperature
55 to +125
65 to +150
C
P
T
Power Dissipation
0.5
0.5
W
I
OUT
DC Output
Current
60 to +120 60 to +120 mA
NOTES:
1. Stresses greater than those listed under ABSOLUTE MAXIMUM RAT-
INGS 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
CC
by +0.5V unless otherwise noted.
2. Input and V
CC
terminals only.
3. Outputs and I/O terminals only.
Symbol
Parameter
(1)
Conditions
Typ.
Max. Unit
C
IN
Input
Capacitance
V
IN
= 0V
6
10
pF
C
OUT
Output
Capacitance
V
OUT
= 0V
8
12
pF
NOTE:
1. This parameter is measured at characterization but not tested.
2537 lnk 03
2537 lnk 04
IDT54/74FCT157T/AT/CT/DT, IDT54/74FCT257T/AT/CT/DT - 2257T/AT/CT
FAST CMOS QUAD 2-INPUT MULTIPLEXER
MILITARY AND COMMERCIAL TEMPERATURE RANGES
6.6
3
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Commercial: T
A
= 0
C to +70
C, V
CC
= 5.0V
5%; Military: T
A
= 55
C to +125
C, V
CC
= 5.0V
10%
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
V
OH
Output HIGH Voltage
V
CC
= Min.
V
IN
= V
IH
or V
IL
I
OH
= 6mA MIL.
I
OH
= 8mA COM'L.
2.4
3.3
--
V
I
OH
= 12mA MIL.
I
OH
= 15mA COM'L.
2.0
3.0
--
V
V
OL
Output LOW Voltage
V
CC
= Min.
V
IN
= V
IH
or V
IL
I
OL
= 32mA MIL.
I
OL
= 48mA COM'L.
--
0.3
0.50
V
I
OS
Short Circuit Current
V
CC
= Max., V
O
= GND
(3)
60
120
225
mA
I
OFF
Input/Output Power Off Leakage
(5)
V
CC
= 0V, V
IN
or V
O
4.5V
--
--
1
A
OUTPUT DRIVE CHARACTERISITICS FOR FCT157/257T
2537 tbl 06
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
I
ODL
Output LOW Current
V
CC
= 5V, V
IN
= V
IH
or
V
IL,
V
OUT
= 1.5V
(3)
16
48
--
mA
I
ODH
Output HIGH Current
V
CC
= 5V, V
IN
= V
IH
or V
IL,
V
OUT
= 1.5V
(3)
16
48
--
mA
V
OH
Output HIGH Voltage
V
CC
= Min.
V
IN
= V
IH
or
V
IL
I
OH
= 12mA MIL.
I
OH
= 15mA COM'L.
2.4
3.3
--
V
V
OL
Output LOW Voltage
V
CC
= Min.
V
IN
= V
IH
or V
IL
I
OL
= 12mA
--
0.3
0.50
V
OUTPUT DRIVE CHARACTERISTICS FOR FCT2257T
2537 lnk 07
NOTES:
1. For conditions shown as Max. or Min., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at Vcc = 5.0V, +25
C ambient.
3. Not more than one output should be shorted at one time. Duration of the short circuit test should not exceed one second.
4. The test limit for this parameter is
5
A at T
A
= 55
C.
5. This parameter is guaranteed but not tested.
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
V
IH
Input HIGH Level
Guaranteed Logic HIGH Level
2.0
--
--
V
V
IL
Input LOW Level
Guaranteed Logic LOW Level
--
--
0.8
V
I
I H
Input HIGH Current
(4)
V
CC
= Max.
V
I
= 2.7V
--
--
1
A
I
I L
Input LOW Current
(4)
V
I
= 0.5V
--
--
1
I
OZH
High Impedance Output Current
V
CC
= Max.
V
O
= 2.7V
--
--
1
A
I
OZL
(3-State Output pins)
(4)
V
O
= 0.5V
--
--
1
I
I
Input HIGH Current
(4)
V
CC
= Max., V
I
= V
CC
(Max.)
--
--
1
A
V
IK
Clamp Diode Voltage
V
CC
= Min., I
IN
= 18mA
--
0.7
1.2
V
V
H
Input Hysteresis
--
--
200
--
mV
I
CC
Quiescent Power Supply Current
V
CC
= Max., V
IN
= GND or V
CC
--
0.01
1
mA
2537 lnk 05
6.6
4
IDT54/74FCT157T/AT/CT/DT, IDT54/74FCT257T/AT/CT/DT- 2257T/AT/CT
FAST CMOS QUAD 2-INPUT MULTIPLEXER
MILITARY AND COMMERCIAL TEMPERATURE RANGES
POWER SUPPLY CHARACTERISTICS
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
I
CC
Quiescent Power Supply Current
TTL Inputs HIGH
V
CC
= Max.
V
IN
= 3.4
(3)
--
0.5
2.0
mA
I
CCD
Dynamic Power Supply Current
(4)
V
CC
= Max.
Outputs Open
E
or
OE
= GND
V
IN
= V
CC
V
IN
= GND
FCTxxxT
--
0.15
0.25
mA/
MHz
One Bit Toggling
50% Duty Cycle
FCT2xxxT
--
0.06
0.12
I
C
Total Power Supply Current
(6)
V
CC
= Max.
V
IN
= V
CC
FCTxxxT
--
1.5
3.5
mA
Outputs Open
V
IN
= GND
FCT2xxxT
--
0.6
2.2
f
O
= 10MHz
50% Duty Cycle
V
IN
= 3.4
FCTxxxT
--
1.8
4.5
E
or
OE
= GND
One Bit Toggling
V
IN
= GND
FCT2xxxT
0.9
3.2
V
CC
= Max.
V
IN
= V
CC
FCTxxxT
--
1.5
3.5
(5)
Outputs Open
V
IN
= GND
FCT2xxxT
0.6
2.2
(5)
f
O
= 2.5MHz
50% Duty Cycle
V
IN
= 3.4
FCTxxxT
2.5
7.5
(5)
E
or
OE
= GND
Four Bits Toggling
V
IN
= GND
FCT2xxxT
1.6
6.2
(5)
NOTES:
1. For conditions shown as Max. or Min., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at V
CC
= 5.0V, +25
C ambient.
3. Per TTL driven input (V
IN
= 3.4V); all other inputs at V
CC
or GND.
4. This parameter is not directly testable, but is derived for use in Total Power Supply calculations.
5. Values for these conditions are examples of the I
CC
formula. These limits are guaranteed but not tested.
6. I
C
= I
QUIESCENT
+ I
INPUTS
+ I
DYNAMIC
I
C
= I
CC
+
I
CC
D
H
N
T
+ I
CCD
(f
o
N
o
)
I
CC
= Quiescent Current
I
CC
= Power Supply Current for a TTL High Input (V
IN
= 3.4V)
D
H
= Duty Cycle for TTL Inputs High
N
T
= Number of TTL Inputs at D
H
I
CCD
= Dynamic Current Caused by an Output Transition Pair (HLH or LHL)
f
o
= Output Frequency
N
o
= Number of Outputs at f
o
All currents are in milliamps and all frequencies are in megahertz.
2537 tbl 06
IDT54/74FCT157T/AT/CT/DT, IDT54/74FCT257T/AT/CT/DT - 2257T/AT/CT
FAST CMOS QUAD 2-INPUT MULTIPLEXER
MILITARY AND COMMERCIAL TEMPERATURE RANGES
6.6
5
SWITCHING CHARACTERISTICS OVER OPERATING RANGE - FCT157T
SWITCHING CHARACTERISTICS OVER OPERATING RANGE FCT257/2257T
2537 tbl 07
2537 tbl 08
2537 tbl 09
NOTES:
2537 tbl 10
1. See test circuits and waveforms.
2. Minimum limits are guaranteed but not tested on Propagation Delay.
FCT257/2257T
FCT257/2257AT
Com'l.
Mil.
Com'l.
Mil.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Min.
(2)
Max.
Min.
(2)
Max.
Min.
(2)
Max.
Unit
t
PLH
t
PHL
Propagation Delay I
N
to Z
N
C
L
= 50pF
R
L
= 500
1.5
6.0
1.5
7.0
1.5
5.0
1.5
5.8
ns
t
PLH
t
PHL
Propagation Delay S to Z
N
1.5
10.5
1.5
12.0
1.5
7.0
1.5
8.1
ns
t
PZH
t
PZL
Output Enable Time
1.5
8.5
1.5
10.0
1.5
7.0
1.5
8.0
ns
t
PHZ
t
PLZ
Output Disable Time
1.5
6.0
1.5
8.0
1.5
5.5
1.5
5.8
ns
FCT257/2257CT
FCT257DT
Com'l.
Mil.
Com'l.
Mil.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Min.
(2)
Max.
Min.
(2)
Max.
Min.
(2)
Max.
Unit
t
PLH
t
PHL
Propagation Delay I
N
to Z
N
C
L
= 50pF
R
L
= 500
1.5
4.3
1.5
5.0
1.5
3.9
--
--
ns
t
PLH
t
PHL
Propagation Delay S to Z
N
1.5
5.2
1.5
6.0
1.5
4.4
--
--
ns
t
PZH
t
PZL
Output Enable Time
1.5
6.0
1.5
6.8
1.5
4.4
--
--
ns
t
PHZ
t
PLZ
Output Disable Time
1.5
5.0
1.5
5.3
1.5
4.4
--
--
ns
FCT157T
FCT157AT
Com'l.
Mil.
Com'l.
Mil.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Min.
(2)
Max.
Min.
(2)
Max.
Min.
(2)
Max.
Unit
t
PLH
t
PHL
Propagation Delay I
N
to Z
N
C
L
= 50pF
R
L
= 500
1.5
6.0
1.5
7.0
1.5
5.0
1.5
5.8
ns
t
PLH
t
PHL
Propagation Delay
E
to Z
N
1.5
10.5
1.5
12.0
1.5
6.0
1.5
7.4
ns
t
PLH
t
PHL
Propagation Delay S to Z
N
1.5
10.5
1.5
12.0
1.5
7.0
1.5
8.1
ns
FCT157CT
FCT157DT
Com'l.
Mil.
Com'l.
Mil.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Min.
(2)
Max.
Min.
(2)
Max.
Min.
(2)
Max.
Unit
t
PLH
t
PHL
Propagation Delay I
N
to Z
N
C
L
= 50pF
R
L
= 500
1.5
4.3
1.5
5.0
1.5
3.9
--
--
ns
t
PLH
t
PHL
Propagation Delay
E
to Z
N
1.5
4.8
1.5
5.9
1.5
4.4
--
--
ns
t
PLH
t
PHL
Propagation Delay S to Z
N
1.5
5.2
1.5
6.0
1.5
4.6
--
--
ns
6.6
6
IDT54/74FCT157T/AT/CT/DT, IDT54/74FCT257T/AT/CT/DT- 2257T/AT/CT
FAST CMOS QUAD 2-INPUT MULTIPLEXER
MILITARY AND COMMERCIAL TEMPERATURE RANGES
TEST CIRCUITS AND WAVEFORMS
TEST CIRCUITS FOR ALL OUTPUTS
ENABLE AND DISABLE TIMES
PROPAGATION DELAY
SET-UP, HOLD AND RELEASE TIMES
PULSE WIDTH
SWITCH POSITION
Pulse
Generator
R
T
D.U.T.
V
CC
V
IN
C
L
V
OUT
50pF
500
500
7.0V
3V
1.5V
0V
3V
1.5V
0V
3V
1.5V
0V
3V
1.5V
0V
DATA
INPUT
TIMING
INPUT
ASYNCHRONOUS CONTROL
PRESET
CLEAR
ETC.
SYNCHRONOUS CONTROL
t
SU
t
H
t
REM
t
SU
t
H
HIGH-LOW-HIGH
PULSE
LOW-HIGH-LOW
PULSE
t
W
1.5V
1.5V
SAME PHASE
INPUT TRANSITION
3V
1.5V
0V
1.5V
V
OH
t
PLH
OUTPUT
OPPOSITE PHASE
INPUT TRANSITION
3V
1.5V
0V
t
PLH
t
PHL
t
PHL
V
OL
CONTROL
INPUT
3V
1.5V
0V
3.5V
0V
OUTPUT
NORMALLY
LOW
OUTPUT
NORMALLY
HIGH
SWITCH
CLOSED
SWITCH
OPEN
V
OL
0.3V
0.3V
t
PLZ
t
PZL
t
PZH
t
PHZ
3.5V
0V
1.5V
1.5V
ENABLE
DISABLE
V
OH
PRESET
CLEAR
CLOCK ENABLE
ETC.
Test
Switch
Disable Low
Enable Low
Closed
All Other Tests
Open
Open Drain
DEFINITIONS:
C
L
=
Load capacitance: includes jig and probe capacitance.
R
T
=
Termination resistance: should be equal to Z
OUT
of the Pulse
Generator.
2537 drw 04
2537 drw 05
2537 drw 06
2537 drw 07
NOTES:
1. Diagram shown for input Control Enable-LOW and input Control Disable-
HIGH
2. Pulse Generator for All Pulses: Rate
1.0MHz; t
F
2.5ns; t
R
2.5ns
2537 drw 08
2537 lnk 11
IDT54/74FCT157T/AT/CT/DT, IDT54/74FCT257T/AT/CT/DT - 2257T/AT/CT
FAST CMOS QUAD 2-INPUT MULTIPLEXER
MILITARY AND COMMERCIAL TEMPERATURE RANGES
6.6
7
ORDERING INFORMATION
2537 drw 09
X
Package
X
Process
Blank
B
Commercial
MIL-STD-883, Class B
P
D
SO
L
E
Q
Plastic DIP
CERDIP
Small Outline IC
Leadless Chip Carrier
CERPACK
Quarter-size Small Outline Package
157T
257T
157AT
257AT
157CT
257CT
157DT
257DT
Quad 2-Input Multiplexer
Quad 2-Input Multiplexer (3-state)
XXXX
Device
Type
55
C to +125
C
0
C to +70
C
54
74
XX
Temperature
Range
FCT
IDT
High Drive
Balanced Drive
Blank
2
X
Family
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