74VHC157
QUAD 2 CHANNEL MULTIPLEXER
PRELIMINARY DATA
June 1999
s
HIGH SPEED: t
PD
= 4.1 ns (TYP.) at V
CC
= 5V
s
LOW POWER DISSIPATION:
I
CC
= 4
A (MAX.) at T
A
= 25
o
C
s
HIGH NOISE IMMUNITY:
V
NIH
= V
NIL
= 28% V
CC
(MIN.)
s
POWER DOWN PROTECTION ON INPUTS
s
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 8 mA (MIN)
s
BALANCED PROPAGATION DELAYS:
t
PLH
t
PHL
s
OPERATING VOLTAGE RANGE:
V
CC
(OPR) = 2V to 5.5V
s
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 157
s
IMPROVED LATCH-UP IMMUNITY
s
LOW NOISE: V
OLP
= 0.8V (Max.)
DESCRIPTION
The 74VHC157 is an high-speed CMOS QUAD
2-CHANNEL
MULTIPLEXER
fabricated
with
sub-micron silicon gate and double-layer metal
wiring C
2
MOS technology.
It consists of four 2-input digital multiplexers with
common select and strobe inputs. It
is a
non-inverting multiplexer. When the STROBE
input is held high, selection of data is inhibited
and all the outputs become low. The SELECT
decoding determines whether the A or B inputs
get routed to their corresponding Y outputs.
Power down protection is provided on all inputs
and 0 to 7V can be accepted on inputs with no
regard to the supply voltage. This device can be
used to interface 5V to 3V.All inputs and outputs
are equipped with protection circuits against static
discharge, giving them 2KV ESD immunity and
transient excess voltage.
PIN CONNECTION AND IEC LOGIC SYMBOLS
M1
(Micro Package)
T
(TSSOP Package)
ORDER CODES :
74VHC157M
74VHC157T
1/9
INPUT EQUIVALENT CIRCUIT
TRUTH TABLE
INPUT
OUT PUT
STROBE
SELE CT
A
B
Y
H
X
X
X
L
L
L
L
X
L
L
L
H
X
H
L
H
X
L
L
L
H
X
H
H
X:"H" or "L"
PIN DESCRIPTION
PIN No
SYMBOL
NAME AND FUNCT ION
1
SELECT
Common Data Select Input
2, 5, 11, 14
1A to 4A
Data Inputs From
Source A
3, 6, 10, 13
1B to 4B
Data Inputs From
Source B
4, 7,9, 12
1Y to 4Y
Multiplexer Outputs
15
STROBE
Strobe Input
8
GND
Ground (0V)
16
V
CC
Positive Supply Voltage
LOGIC DIAGRAM
74VHC157
2/9
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Val ue
Unit
V
CC
Supply Voltage
-0.5 to +7.0
V
V
I
DC Input Voltage
-0.5 to +7.0
V
V
O
DC Output Voltage
-0.5 to V
CC
+ 0.5
V
I
IK
DC Input Diode Current
- 20
mA
I
OK
DC Output Diode Current
20
mA
I
O
DC Output Current
25
mA
I
CC
orI
GND
DC V
CC
or Ground Current
50
mA
T
stg
Storage Temperature
-65 to +150
o
C
T
L
Lead Temperature (10 sec)
300
o
C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied.
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Valu e
Uni t
V
CC
Supply Voltage
2.0 to 5.5
V
V
I
Input Voltage
0 to 5.5
V
V
O
Output Voltage
0 to V
CC
V
T
op
Operating Temperature
-40 to +85
o
C
dt/dv
Input Rise and Fall Time (see note 1) (V
CC
= 3.3
0.3V)
(V
CC
= 5.0
0.5V)
0 to 100
0 to 20
ns/V
ns/V
1) V
IN
from 30% to70%of V
CC
DC SPECIFICATIONS
Symb ol
Parameter
T est Cond ition s
Val ue
Un it
V
CC
(V)
T
A
= 25
o
C
-40 to 85
o
C
Min.
Typ .
Max.
Min .
Max.
V
IH
High Level Input
Voltage
2.0
1.5
1.5
V
3.0 to 5.5
0.7V
CC
0.7V
CC
V
IL
Low Level Input
Voltage
2.0
0.5
0.5
V
3.0 to 5.5
0.3V
CC
0.3V
CC
V
OH
High Level Output
Voltage
2.0
I
O
=-50
A
1.9
2.0
1.9
V
3.0
I
O
=-50
A
2.9
3.0
2.9
4.5
I
O
=-50
A
4.4
4.5
4.4
3.0
I
O
=-4 mA
2.58
2.48
4.5
I
O
=-8 mA
3.94
3.8
V
OL
Low Level Output
Voltage
2.0
I
O
=50
A
0.0
0.1
0.1
V
3.0
I
O
=50
A
0.0
0.1
0.1
4.5
I
O
=50
A
0.0
0.1
0.1
3.0
I
O
=4 mA
0.36
0.44
4.5
I
O
=8 mA
0.36
0.44
I
I
Input Leakage Current
0 to 5.5
V
I
= 5.5V or GND
0.1
1.0
A
I
CC
Quiescent Supply
Current
5.5
V
I
= V
CC
orGND
4
40
A
74VHC157
3/9
CAPACITIVE CHARACTERISTICS
Symb ol
Parameter
T est Cond ition s
Val ue
Un it
T
A
= 25
o
C
-40 to 85
o
C
Min.
Typ .
Max.
Min .
Max.
C
IN
Input Capacitance
4
10
10
pF
C
PD
Power Dissipation
Capacitance (note 1)
20
pF
1) C
PD
isdefined as the value of the IC'sinternal equivalent capacitance which is calculated fromthe operating current consumption without load. (Referto
Test Circuit).Average operating current can be obtained by the following equation. I
CC
(opr) = C
PD
V
CC
f
IN
+ I
CC
/4 (per Channel)
AC ELECTRICAL CHARACTERISTICS (Input t
r
= t
f
=3 ns)
Symb ol
Parameter
Test Co nditi on
Val ue
Un it
V
CC
(V)
C
L
(pF )
T
A
= 25
o
C
-40 to 85
o
C
Min.
Typ .
Max.
Min .
Max.
t
PLH
t
PHL
Propagation Delay
Time
A, B to Y
3.3
(*)
15
6.2
9.7
1.0
11.5
ns
3.3
(*)
50
8.7
13.2
1.0
15.0
5.0
(**)
15
4.1
6.4
1.0
7.5
5.0
(**)
50
5.6
8.4
1.0
9.5
t
PLH
t
PHL
Propagation Delay
Time
SELECT to Y
3.3
(*)
15
8.4
13.2
1.0
15.5
ns
3.3
(*)
50
10.9
16.7
1.0
19.0
5.0
(**)
15
5.3
8.1
1.0
9.5
5.0
(**)
50
6.8
10.1
1.0
11.5
t
PLH
t
PHL
Propagation Delay
Time
STROBE to Y
3.3
(*)
15
8.7
13.6
1.0
16.0
ns
3.3
(*)
50
11.2
17.1
1.0
19.5
5.0
(**)
15
5.6
8.6
1.0
10.0
5.0
(**)
50
7.1
10.6
1.0
12.0
(*) Voltage range is 3.3V
0.3V
(**) Voltage range is 5V
0.5V
74VHC157
4/9
DYNAMIC SWITCHING CHARACTERISTICS
Symb ol
Parameter
T est Cond ition s
Val ue
Un it
V
CC
(V)
T
A
= 25
o
C
-40 to 85
o
C
Min.
Typ .
Max.
Min .
Max.
V
OLP
Dynamic Low Voltage
Quiet Output (note 1, 2)
5.0
C
L
= 50 pF
0.3
0.8
V
V
OLV
-0.8
-0.3
V
IHD
Dynamic High Voltage
Input (note 1, 3)
5.0
3.5
V
ILD
Dynamic Low Voltage
Input (note 1, 3)
5.0
1.5
1) Worst case package.
2) Max number of outputs defined as (n). Data inputs are driven 0V to 5.0V, (n -1) outputs switching and one output at GND.
3) Max number of data inputs (n) switching. (n-1) switching 0V to5.0V. Inputs under test switching: 5.0V to threshold (V
ILD
), 0V to threshold (V
IHD
), f=1MHz.
TEST CIRCUIT
C
L
= 15/50 pF or equivalent (includes jig and probe capacitance)
R
T
= Z
OUT
of pulse generator (typically 50
)
74VHC157
5/9
WAVEFORM 1: PROPAGATION DELAYS FOR INVERTING CONDITIONS
WAVEFORM 2: PROPAGATION DELAYS FOR NON-INVERTING CONDITIONS
74VHC157
6/9
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
1.75
0.068
a1
0.1
0.2
0.004
0.007
a2
1.65
0.064
b
0.35
0.46
0.013
0.018
b1
0.19
0.25
0.007
0.010
C
0.5
0.019
c1
45 (typ.)
D
9.8
10
0.385
0.393
E
5.8
6.2
0.228
0.244
e
1.27
0.050
e3
8.89
0.350
F
3.8
4.0
0.149
0.157
G
4.6
5.3
0.181
0.208
L
0.5
1.27
0.019
0.050
M
0.62
0.024
S
8 (max.)
P013H
SO-16 MECHANICAL DATA
74VHC157
7/9
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
1.1
0.433
A1
0.05
0.10
0.15
0.002
0.004
0.006
A2
0.85
0.9
0.95
0.335
0.354
0.374
b
0.19
0.30
0.0075
0.0118
c
0.09
0.20
0.0035
0.0079
D
4.9
5
5.1
0.193
0.197
0.201
E
6.25
6.4
6.5
0.246
0.252
0.256
E1
4.3
4.4
4.48
0.169
0.173
0.176
e
0.65 BSC
0.0256 BSC
K
0
o
4
o
8
o
0
o
4
o
8
o
L
0.50
0.60
0.70
0.020
0.024
0.028
c
E
b
A2
A
E1
D
1
PIN 1 IDENTIFICATION
A1
L
K
e
TSSOP16 MECHANICAL DATA
74VHC157
8/9
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is
granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are
subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products
are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
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1999 STMicroelectronics Printed in Italy All Rights Reserved
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