Page 1
QUAD 2 CHANNEL MULTIPLEXER
■ HIGHSPEED:t
■ LOW POWER DISSIPATION:
=4 µA(MAX.)atTA=25oC
I
CC
■ COMPATIBLEWITHTTL OUTPUTS:
=2V(MIN),VIL=0.8V(MAX)
V
IH
■ POWERDOWNPROTECTIONON INPUTS&
OUTPUTS
■ SYMMETRICALOUTPUTIMPEDANCE:
|I
|=IOL=8 mA(MIN)
OH
■ BALANCEDPROPAGATIONDELAYS:
t
≅ t
PLH
PHL
■ OPERATINGVOLTAGERANGE:
(OPR)= 4.5Vto 5.5V
V
CC
■ PINANDFUNCTIONCOMPATIBLEWITH
74SERIES157
■ IMPROVEDLATCH-UP IMMUNITY
■ LOWNOISE:V
DESCRIPTION
The 74VHCT157A is an high-speed CMOS
QUAD 2-CHANNEL MULTIPLEXER fabricated
with sub-micron silicon gate and double-layer
metalwiring C
It consists of four 2-input digital multiplexers with
common select and strobe inputs. It is a
=6.2ns (TYP.)atVCC=5V
PD
= 0.8V(Max.)
OLP
2
MOStechnology.
74VHCT157A
PRELIMINARY DATA
SOP TSSOP
ORDER CODES
PACKAGE TUBE T & R
SOP 74VHCT157AM 74VHCT157AMTR
TSSOP 74VH C T157 ATTR
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 Youtputs.
Power down protection is provided on all inputs
and outputs 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 transientexcess voltage.
PIN CONNECTION AND IEC LOGICSYMBOLS
March 2000
1/9
Page 2
74VHCT157A
INPUT EQUIVALENTCIRCUIT
PIN DESCRIPTION
PI N No SYM BO L NAM E AND FUNCT I O N
1 SELECT Common Data Select Input
2,5,11,14 1Ato4A Data Inputs From
Source A
3,6,10,13 1Bto4B Data Inputs From
Source B
4,7,9,12 1Yto4Y Multiplexer Outputs
15 STROBE Strobe Input
8 GND Ground (0V)
16 V
Positive Supply Voltage
CC
TRUTH TABLE
INPUT OUTPUT
STROBE SELECT A B Y
HXXXL
LLLXL
LLHXH
LHXLL
LHXHH
X:”H” or”L”
LOGICDIAGRAM
2/9
Page 3
74VHCT157A
ABSOLUTE MAXIMUM RATINGS
Symb o l Para met er Value U n i t
V
V
V
V
I
I
OK
I
orI
I
CC
T
T
AbsoluteMaximumRatingsarethosevaluesbeyond whichdamagetothedevicemayoccur. Functional operationundertheseconditionisnotimplied.
1)V
=0
CC
2)HighorLowState
RECOMMENDED OPERATINGCONDITIONS
Symb o l Para met er Value Unit
V
V
V
V
T
dt/dv
1)VCC=0
2)HighorLowState
from0.8Vto 2V
3)V
IN
Supply Voltage -0.5to+7.0 V
CC
DC Input Voltage -0.5to+7.0 V
I
DC Output Voltage (see note 1) -0.5to+7.0 V
O
DC Output Voltage (see note 2) -0.5toVCC+0.5 V
O
DC Input Diode Current -20 mA
IK
DC Output Diode Current
DC Output Current
O
DC VCCor Ground Current ±50 mA
GND
Storage Temperature -65to+150
stg
Lead Temperature (10 sec) 300
L
Supply Voltage 4.5to5.5 V
CC
Input Voltage 0to5.5 V
I
Output Voltage (see note 1) 0to5.5 V
O
Output Voltage (see note 2) 0toV
O
Operating Temperature -40to+85
op
Input Rise and Fall Time (see note 3) (V
=5.0±0.5V)
CC
20 mA
±
25 mA
±
CC
0to20 ns/V
o
C
o
C
V
o
C
DC SPECIFICATIONS
Symb o l Para met er Test C o n dit io ns Val u e Unit
T
V
CC
High Level Input
V
IH
(V)
4.5to5.5 2 2 V
Min. Typ. Max. Min. Max.
Voltage
Low Level Input
V
IL
4.5to5.5 0.8 0.8 V
Voltage
High Level Output
V
OH
Voltage
Low Level Output
V
OL
Voltage
Input Leakage Current 0to5.5 VI=5.5VorGND ±0.1 ±1.0 µA
I
I
Quiescent Supply
I
CC
4.5 IO=-50µA4.44.5 4.4
4.5 I
=-8mA 3.94 3.8
O
4.5 IO=50µA 0.0 0.1 0.1
4.5 I
=8mA 0.36 0.44
O
5.5 VI=VCCorGND 4 40
Current
Additional Worst Case
∆I
CC
Supply Current
5.5 One Input at3.4V,
other input at V
CC
or
GND
I
OPD
Output Leakage
0V
=5.5V 0.5 5.0 µA
OUT
Current
=25oC -40 to 85oC
A
1.35 1.5 mA
µ
V
V
A
3/9
Page 4
74VHCT157A
AC ELECTRICAL CHARACTERISTICS
(Inputt
r=tf
=3 ns)
Symbol Parameter Test Conditi on Value Unit
t
Propagation Delay
PLH
t
Time
PHL
V
(V)
5.0
5.0
CC
C
L
(pF)
(*)
(*)
15 6.2 9.7 1.0 11.5
50 8.7 13.2 1.0 15.0
T
=25oC -40 to 85oC
A
Min. Typ. Max. Min. Max.
ns
A, B to Y
Propagation Delay
t
PLH
t
Time
PHL
SELECT to Y
Propagation Delay
t
PLH
t
Time
PHL
5.0
5.0
5.0
5.0
(*)
(*)
(*)
(*)
15 8.4 13.2 1.0 15.5
50 10.9 16.7 1.0 19.0
15 8.7 13.6 1.0 16.0
50 11.2 17.1 1.0 19.5
ns
ns
STROBE to Y
(*)Voltagerange is5V± 0.5V
CAPACITIVE CHARACTERISTICS
Symb o l Para met er Test C o n dit io ns Val u e Unit
=25oC -40 to 85oC
T
A
Min. Typ. Max. Min. Max.
Input Capacitance 4 10 10
C
IN
Power Dissipation
C
PD
20 pF
Capacitance (note 1)
1)CPDisdefinedas thevalueoftheIC’sinternal equivalent capacitance whichis calculatedfromtheoperatingcurrent consumption without load.(Referto
TestCircuit).Averageoperatingcurrentcanbeobtained bythefollowingequation.I
(opr)=CPD• VCC• fIN+ICC/4 (per Channel)
CC
pF
4/9
Page 5
74VHCT157A
DYNAMICSWITCHING CHARACTERISTICS
Symb o l Para met er Test C o n dit io ns Val u e Unit
T
V
CC
(V)
V
V
Dynamic Low Voltage
OLP
Quiet Output (note 1, 2)
OLV
Dynamic High Voltage
V
IHD
5.0
5.0 2.0
C
=50pF
L
Min. Typ. Max. Min. Max.
Input (note 1, 3)
Dynamic Low Voltage
V
ILD
5.0 0.8
Input (note 1, 3)
1)Worstcasepackage.
2)Maxnumberofoutputsdefined as(n).Datainputsaredriven0Vto 5.0V,(n-1)outputs switching andoneoutputatGND.
3)Maxnumberofdatainputs (n)switching.(n-1)switching0Vto5.0V. Inputsunder testswitching: 5.0Vtothreshold(V
TESTCIRCUIT
=25oC -40 to 85oC
A
0.3 0.8
-0.8 -0.3
),0Vtothreshold(V
ILD
),f=1MHz.
IHD
V
CL= 15/50 pF or equivalent (includes jigand probe capacitance)
R
ofpulsegenerator(typically50Ω)
T=ZOUT
5/9
Page 6
74VHCT157A
WAVEFORM 1: PROPAGATIONDELAYS FORINVERTING CONDITIONS
WAVEFORM 2: PROPAGATIONDELAYS FORNON-INVERTING CONDITIONS
6/9
Page 7
SO-16 MECHANICALDATA
74VHCT157A
DIM.
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.)
mm inch
P013H
7/9
Page 8
74VHCT157A
TSSOP16 MECHANICAL DATA
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
K0
o
o
4
o
8
o
0
o
4
L 0.50 0.60 0.70 0.020 0.024 0.028
o
8
A
PIN 1 IDENTIFICATION
8/9
A2
A1
b
e
c
K
L
E
D
E1
1
Page 9
74VHCT157A
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