FAST CMOS
QUAD 2-INPUT
MULTIPLEXER
Integrated Device Technology, Inc.
IDT54/74FCT157T/AT/CT/DT
IDT54/74FCT257T/AT/CT/DT
IDT54/74FCT2257T/AT/CT
FEATURES:
• Common features:
– Low input and output leakage
≤1µA
(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
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
PIN CONFIGURATIONS
S
I
0A
I
1A
Z
A
I
0B
I
1B
Z
B
GND
1
2
3
4
5
6
7
8
16
15
157 Only
E
3 other multiplexers
P16-1,
D16-1,
SO16-1,
SO16-7
&
E16-1
14
13
12
11
10
9
I
1B
–I
1D
I
0B
–I
0D
Z
B
–Z
D
Vcc
E or OE*
I
0C
I
1C
Z
C
I
0D
I
1D
Z
D
2537 drw 02
DIP/SOIC/QSOP/CERPACK
TOP VIEW
Z
A
I
0A
S
NC
Vcc
E or OE*
3
2
4
5
6
7
8
I
1A
I
0A
257 Only
OE
INDEX
2537 drw 01
I
1A
Z
A
NC
I
0B
I
1B
L20-2
20 19
18
1
17
16
15
14
10 11 12 13
9
I
0C
I
1C
NC
Z
C
I
0D
LCC
TOP VIEW
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
Z
B
GND
NC
Z
D
I
1D
2537 drw 03
*
E
for FCT157,
OE
for FCT257/FCT2257.
MILITARY AND COMMERCIAL TEMPERATURE RANGES
©1996
Integrated Device Technology, Inc.
JUNE 1996
2537/6
6.6
1
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
I
0A
–I
0D
I
1A
–I
1D
E
OE
FUNCTION TABLE
(1)
Description
Inputs
E OE
Output Z
N
I
0
X
X
X
L
H
I
1
X
L
H
X
X
157
L
L
H
L
H
257
Z
L
H
L
H
2537 tbl 02
Source 0 Data Inputs
Source 1 Data Inputs
Enable Input (Active LOW)–FCT157T
Output Enable (Active LOW)–FCT257T/2257T
Select Input
Outputs
2537 tbl 01
/
S
X
H
H
L
L
H
L
L
L
L
S
Z
A
–Z
D
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
X = Don’t Care
Z = High Impedance
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
Rating
Commercial
(2)
Terminal Voltage
V
TERM
–0.5 to +7.0
with Respect to
GND
V
TERM(3)
Terminal Voltage
–0.5 to
with Respect to
V
CC
+0.5
GND
T
A
Operating
0 to +70
Temperature
T
BIAS
Temperature
–55 to +125
Under Bias
T
STG
Storage
–55 to +125
Temperature
P
T
Power Dissipation
0.5
I
OUT
DC Output
Current
–60 to +120
Military
–0.5 to +7.0
Unit
V
CAPACITANCE
(T
A
= +25°C, f = 1.0MHz)
Symbol
Parameter
(1)
C
IN
Input
Capacitance
C
OUT
Output
Capacitance
Conditions
V
IN
= 0V
V
OUT
= 0V
Typ.
6
8
Max. Unit
10
pF
12
pF
2537 lnk 04
–0.5 to
V
CC
+0.5
–55 to +125
–65 to +135
–65 to +150
0.5
–60 to +120
V
°C
°C
°C
W
mA
NOTE:
1. This parameter is measured at characterization but not tested.
2537 lnk 03
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.
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
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
V
IH
V
IL
I
I H
I
I L
I
OZH
I
OZL
I
I
V
IK
V
H
I
CC
Parameter
Input HIGH Level
Input LOW Level
Input HIGH Current
(4)
Input LOW Current
(4)
High Impedance Output Current
(3-State Output pins)
(4)
Input HIGH Current
(4)
Clamp Diode Voltage
Input Hysteresis
Quiescent Power Supply Current
V
CC
= Min., I
IN
= –18mA
—
Test Conditions
(1)
Guaranteed Logic HIGH Level
Guaranteed Logic LOW Level
V
CC
= Max.
V
CC
= Max.
V
I
= 2.7V
V
I
= 0.5V
V
O
= 2.7V
V
O
= 0.5V
V
CC
= Max., V
I
= V
CC
(Max.)
Min.
2.0
—
—
—
—
—
—
—
—
—
Typ.
(2)
—
—
—
—
—
—
—
–0.7
200
0.01
Max.
—
0.8
Unit
V
V
±
1
±
1
±
1
±
1
±
1
–1.2
—
1
µ
A
µ
A
µ
A
V
mV
mA
2537 lnk 05
V
CC
= Max., V
IN
= GND or V
CC
OUTPUT DRIVE CHARACTERISITICS FOR FCT157/257T
Symbol
V
OH
Parameter
Output HIGH Voltage
Test Conditions
(1)
V
CC
= Min.
I
OH
= –6mA MIL.
V
IN
= V
IH
or V
IL
I
OH
= –8mA COM'L.
I
OH
= –12mA MIL.
I
OH
= –15mA COM'L.
V
CC
= Min.
I
OL
= 32mA MIL.
V
IN
= V
IH
or V
IL
I
OL
= 48mA COM'L.
V
CC
= Max., V
O
= GND
(3)
V
CC
= 0V, V
IN
or V
O
≤
4.5V
Min.
2.4
2.0
—
–60
—
Typ.
(2)
3.3
3.0
0.3
–120
—
Max.
—
—
0.50
–225
Unit
V
V
V
mA
V
OL
I
OS
I
OFF
Output LOW Voltage
Short Circuit Current
Input/Output Power Off Leakage
(5)
±
1
µ
A
2537 tbl 06
OUTPUT DRIVE CHARACTERISTICS FOR FCT2257T
Symbol
I
ODL
I
ODH
V
OH
V
OL
Parameter
Output LOW Current
Output HIGH Current
Output HIGH Voltage
Output LOW Voltage
Test Conditions
(1)
V
CC
= 5V, V
IN
= V
IH
or V
IL,
V
OUT
= 1.5V
(3)
V
CC
= 5V, V
IN
= V
IH
or V
IL,
V
OUT
= 1.5V
(3)
V
CC
= Min.
V
IN
= V
IH
or V
IL
V
CC
= Min.
V
IN
= V
IH
or V
IL
I
OH
= –12mA MIL.
I
OH
= –15mA COM'L.
I
OL
= 12mA
Min.
16
–16
2.4
—
Typ.
(2)
48
–48
3.3
0.3
Max.
—
—
—
0.50
Unit
mA
mA
V
V
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
±5µA
at T
A
= –55°C.
5. This parameter is guaranteed but not tested.
6.6
3
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
∆I
CC
I
CCD
Parameter
Quiescent Power Supply Current
TTL Inputs HIGH
Dynamic Power Supply Current
(4)
Test Conditions
(1)
V
CC
= Max.
V
IN
= 3.4
(3)
V
CC
= Max.
Outputs Open
E
or
OE
= GND
One Bit Toggling
50% Duty Cycle
V
CC
= Max.
Outputs Open
f
O
= 10MHz
50% Duty Cycle
E
Min.
—
FCTxxxT
—
Typ.
(2)
0.5
0.15
Max.
2.0
0.25
Unit
mA
mA/
MHz
V
IN
= V
CC
V
IN
= GND
FCT2xxxT
V
IN
= V
CC
V
IN
= GND
V
IN
= 3.4
V
IN
= GND
V
IN
= V
CC
V
IN
= GND
V
IN
= 3.4
V
IN
= GND
FCTxxxT
FCT2xxxT
FCTxxxT
FCT2xxxT
FCTxxxT
FCT2xxxT
FCTxxxT
FCT2xxxT
—
—
—
—
0.06
1.5
0.6
1.8
0.9
0.12
3.5
2.2
4.5
3.2
3.5
(5)
2.2
(5)
7.5
(5)
6.2
(5)
2537 tbl 06
I
C
Total Power Supply Current
(6)
mA
or
OE
= GND
—
1.5
0.6
2.5
1.6
One Bit Toggling
V
CC
= Max.
Outputs Open
f
O
= 2.5MHz
50% Duty Cycle
E
or
OE
= GND
Four Bits Toggling
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.
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
SWITCHING CHARACTERISTICS OVER OPERATING RANGE - FCT157T
FCT157T
Com'l.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Mil.
Min.
(2)
Max.
Com'l.
Min.
(2)
Max.
FCT157AT
Mil.
Min.
(2)
Max.
Unit
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
Propagation Delay I
N
to Z
N
Propagation Delay
E
to Z
N
Propagation Delay S to Z
N
C
L
= 50pF
R
L
= 500
Ω
1.5
1.5
1.5
6.0
10.5
10.5
1.5
1.5
1.5
7.0
12.0
12.0
1.5
1.5
1.5
5.0
6.0
7.0
1.5
1.5
1.5
5.8
7.4
8.1
ns
ns
ns
2537 tbl 07
FCT157CT
Com'l.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Mil.
Min.
(2)
Max.
Com'l.
Min.
(2)
FCT157DT
Mil.
Min.
(2)
Max.
Unit
Max.
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
Propagation Delay I
N
to Z
N
Propagation Delay
E
to Z
N
Propagation Delay S to Z
N
C
L
= 50pF
R
L
= 500
Ω
1.5
1.5
1.5
4.3
4.8
5.2
1.5
1.5
1.5
5.0
5.9
6.0
1.5
1.5
1.5
3.9
4.4
4.6
—
—
—
—
—
—
ns
ns
ns
2537 tbl 08
SWITCHING CHARACTERISTICS OVER OPERATING RANGE – FCT257/2257T
FCT257/2257T
Com'l.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Mil.
Min.
(2)
Max.
FCT257/2257AT
Com'l.
Min.
(2)
Max.
Mil.
Min.
(2)
Max.
Unit
t
PLH
t
PHL
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
Propagation Delay I
N
to Z
N
Propagation Delay S to Z
N
Output Enable Time
Output Disable Time
C
L
= 50pF
R
L
= 500Ω
1.5
1.5
1.5
1.5
6.0
10.5
8.5
6.0
1.5
1.5
1.5
1.5
7.0
12.0
10.0
8.0
1.5
1.5
1.5
1.5
5.0
7.0
7.0
5.5
1.5
1.5
1.5
1.5
5.8
8.1
8.0
5.8
ns
ns
ns
ns
2537 tbl 09
FCT257/2257CT
Com'l.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Mil.
Min.
(2)
Max.
Com'l.
Min.
(2)
FCT257DT
Mil.
Min.
(2)
Max.
Unit
Max.
t
PLH
t
PHL
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
Propagation Delay I
N
to Z
N
Propagation Delay S to Z
N
Output Enable Time
Output Disable Time
C
L
= 50pF
R
L
= 500Ω
1.5
1.5
1.5
1.5
4.3
5.2
6.0
5.0
1.5
1.5
1.5
1.5
5.0
6.0
6.8
5.3
1.5
1.5
1.5
1.5
3.9
4.4
4.4
4.4
—
—
—
—
—
—
—
—
ns
ns
ns
ns
2537 tbl 10
NOTES:
1. See test circuits and waveforms.
2. Minimum limits are guaranteed but not tested on Propagation Delay.
6.6
5
PCB设计
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
