M74HCT157
QUAD 2 CHANNEL MULTIPLEXER
s
s
s
s
s
s
HIGH SPEED:
t
PD
= 16ns (TYP.) at V
CC
= 4.5V
LOW POWER DISSIPATION:
I
CC
= 4µA(MAX.) at T
A
=25°C
COMPATIBLE WITH TTL OUTPUTS :
V
IH
= 2V (MIN.) V
IL
= 0.8V (MAX)
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 4mA (MIN)
BALANCED PROPAGATION DELAYS:
t
PLH
≅
t
PHL
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 157
DIP
SOP
ORDER CODES
PACKAGE
DIP
SOP
TSSOP
TUBE
DESCRIPTION
The M74HCT157 is an high speed CMOS QUAD
2 CHANNEL MULTIPLEXER fabricated with
silicon gate C
2
MOS technology.
This device consists of four 2-input digital
multiplexer with common select and strobe inputs.
When the STROBE(ST) input is held high,
selection of data is inhibited and all the outputs
become low. The SELECT decoding determines
bs
O
et
l
o
ro
P
e
uc
d
s)
t(
O
-
whether the A or B inputs get routed to their
corresponding Y outputs.
All inputs are equipped with protection circuits
against static discharge and transient excess
voltage.
so
b
te
le
M74HCT157B1R
M74HCT157M1R
ro
P
uc
d
s)
t(
TSSOP
T&R
M74HCT157RM13TR
M74HCT157TTR
PIN CONNECTION AND IEC LOGIC SYMBOLS
September 2001
1/9
M74HCT157
ABSOLUTE MAXIMUM RATINGS
Symbol
V
CC
V
I
V
O
I
IK
I
OK
I
O
Supply Voltage
DC Input Voltage
DC Output Voltage
DC Input Diode Current
DC Output Diode Current
DC Output Current
Parameter
Value
-0.5 to +7
-0.5 to V
CC
+ 0.5
-0.5 to V
CC
+ 0.5
±
20
±
20
±
25
±
50
500(*)
-65 to +150
300
Unit
V
V
V
mA
mA
mA
mA
I
CC
or I
GND
DC V
CC
or Ground Current
P
D
Power Dissipation
T
stg
T
L
Storage Temperature
Lead Temperature (10 sec)
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied
(*) 500mW at 65
°
C; derate to 300mW by 10mW/
°
C from 65
°
C to 85
°
C
RECOMMENDED OPERATING CONDITIONS
Symbol
V
CC
V
I
V
O
T
op
t
r
, t
f
Supply Voltage
Input Voltage
Output Voltage
Operating Temperature
Parameter
Input Rise and Fall Time (V
CC
= 4.5 to 5.5V)
bs
O
et
l
o
ro
P
e
uc
d
)-
(s
t
b
O
so
te
le
r
P
du
o
Value
ct
s)
(
mW
°C
°C
Unit
V
V
V
°C
ns
4.5 to 5.5
0 to V
CC
0 to V
CC
-55 to 125
0 to 500
3/9
M74HCT157
DC SPECIFICATIONS
Test Condition
Symbol
Parameter
V
CC
(V)
4.5
to
5.5
4.5
to
5.5
4.5
4.5
5.5
5.5
5.5
I
O
=-20
µA
I
O
=-4.0 mA
I
O
=20
µA
I
O
=4.0 mA
V
I
= V
CC
or GND
V
I
= V
CC
or GND
Per Input pin
V
I
= 0.5V or
V
I
= 2.4V
Other Inputs at
V
CC
or GND
I
O
= 0
T
A
= 25°C
Min.
2.0
Typ.
Max.
Value
-40 to 85°C
Min.
2.0
Max.
-55 to 125°C
Min.
2.0
Max.
V
Unit
V
IH
High Level Input
Voltage
Low Level Input
Voltage
High Level Output
Voltage
Low Level Output
Voltage
Input Leakage
Current
Quiescent Supply
Current
Additional Worst
Case Supply
Current
V
IL
0.8
4.4
4.18
4.5
4.31
0.0
0.17
0.1
0.26
±
0.1
4.4
4.13
0.8
4.4
4.10
0.1
0.8
V
V
OH
V
OL
I
I
I
CC
∆
I
CC
* : Applicable only to DIR, G, G input
AC ELECTRICAL CHARACTERISTICS
(C
L
= 50 pF, Input t
r
= t
f
= 6ns)
Symbol
Parameter
b
O
t
TLH
t
THL
Output Transition
Time
t
PLH
t
PHL
Propagation Delay
Time (A, B - Y)
t
PLH
t
PHL
Propagation Delay
Time (SELECT - Y)
t
PLH
t
PHL
Propagation Delay
Time (STROBE -Y)
et
l
so
ro
P
e
uc
d
V
CC
(V)
4.5
4.5
4.5
4.5
Test Condition
T
A
= 25°C
Min.
Typ.
8
16
19
17
Max.
15
25
30
27
s)
t(
O
-
so
b
te
le
2.0
4
r
P
du
o
0.33
±
1
40
2.9
ct
0.1
s)
(
80
V
V
0.40
±
1
µA
µA
mA
3.0
Value
-40 to 85°C
Min.
Max.
19
31
38
34
-55 to 125°C
Min.
Max.
22
38
45
41
ns
ns
ns
ns
Unit
4/9
M74HCT157
CAPACITIVE CHARACTERISTICS
Test Condition
Symbol
Parameter
V
CC
(V)
5.0
5.0
T
A
= 25°C
Min.
Typ.
5
50
Max.
10
Value
-40 to 85°C
Min.
Max.
10
-55 to 125°C
Min.
Max.
10
pF
pF
Unit
C
IN
C
PD
Input Capacitance
Power Dissipation
Capacitance (note
1)
1) C
PD
is defined as the value of the IC’s internal equivalent capacitance which is calculated from the operating current consumption without
load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. I
CC(opr)
= C
PD
x V
CC
x f
IN
+ I
CC
/4(per chan-
nel)
TEST CIRCUIT
C
L
= 50pF or equivalent (includes jig and probe capacitance)
R
T
= Z
OUT
of pulse generator (typically 50Ω)
WAVEFORM : PROPAGATION DELAY TIMES
(f=1MHz; 50% duty cycle)
bs
O
et
l
o
ro
P
e
uc
d
s)
t(
O
-
so
b
te
le
ro
P
uc
d
s)
t(
5/9
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