DataSheet26.com

74S138 PDF даташит

Спецификация 74S138 изготовлена ​​​​«Fairchild Semiconductor» и имеет функцию, называемую «(74S138 / 74S139) Decoder / Demultiplexer».

Детали детали

Номер произв 74S138
Описание (74S138 / 74S139) Decoder / Demultiplexer
Производители Fairchild Semiconductor
логотип Fairchild Semiconductor логотип 

5 Pages
scroll

No Preview Available !

74S138 Даташит, Описание, Даташиты
August 1986
Revised April 2000
DM74S138 DM74S139
Decoder/Demultiplexer
General Description
These Schottky-clamped circuits are designed to be used
in high-performance memory-decoding or data-routing
applications, requiring very short propagation delay times.
In high-performance memory systems these decoders can
be used to minimize the effects of system decoding. When
used with high-speed memories, the delay times of these
decoders are usually less than the typical access time of
the memory. This means that the effective system delay
introduced by the decoder is negligible.
The DM74S138 decodes one-of-eight lines, based upon
the conditions at the three binary select inputs and the
three enable inputs. Two active-LOW and one active-HIGH
enable inputs reduce the need for external gates or invert-
ers when expanding. A 24-line decoder can be imple-
mented with no external inverters, and a 32-line decoder
requires only one inverter. An enable input can be used as
a data input for demultiplexing applications.
The DM74S139 comprises two separate two-line-to-four-
line decoders in a single package. The active-LOW enable
input can be used as a data line in demultiplexing applica-
tions.
All of these decoders/demultiplexers feature fully buffered
inputs, presenting only one normalized load to its driving
circuit. All inputs are clamped with high-performance
Schottky diodes to suppress line-ringing and simplify sys-
tem design.
Features
s Designed specifically for high speed:
Memory decoders
Data transmission systems
s DM74S138 3-to-8-line decoders incorporates 3 enable
inputs to simplify cascading and/or data reception
s DM74S139 contains two fully independent 2-to-4-line
decoders/demultiplexers
s Schottky clamped for high performance
s Typical propagation delay time (3 levels of logic)
DM74S138 8 ns
DM74S139 7.5 ns
s Typical power dissipation
DM74S138 245 mW
DM74S139 300 mW
Ordering Code:
Order Number
DM74S138N
DM74S139N
Package Number
Package Description
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
© 2000 Fairchild Semiconductor Corporation DS006466
www.fairchildsemi.com
Free Datasheet http://www.Datasheet4U.com









No Preview Available !

74S138 Даташит, Описание, Даташиты
Connection Diagrams
DM74S138
DM74S139
Function Tables
DM74S138
Inputs
Enable Select
Outputs
G1 G2* C B A Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
X H XXX H H H H H H H H
L X XXX H H H H H H H H
H L LLL L H H H H H H H
H L LLH H L H H H H H H
H L LHL H H L H H H H H
H L LHH H H H L H H H H
H L HLL H H H H L H H H
H L HLH H H H H H L H H
H L HH L H H H H H H L H
H L HHH H H H H H H H L
Logic Diagrams
DM74S139
Inputs
Enable
Select
G BA
H XX
L LL
L LH
L HL
L HH
Y0
H
L
H
H
H
Outputs
Y1 Y2
HH
HH
LH
HL
HH
* G2 = G2A + G2B
H = HIGH level
L = LOW level
X = don’t care (either LOW or HIGH logic level)
DM74S138
DM74S139
Y3
H
H
H
H
L
www.fairchildsemi.com
2
Free
Datashe









No Preview Available !

74S138 Даташит, Описание, Даташиты
Absolute Maximum Ratings(Note 1)
Supply Voltage
7V
Input Voltage
5.5V
Operating Free Air Temperature Range
0° C to +70°C
Storage Temperature Range
65° C to +150° C
Note 1: The Absolute Maximum Ratingsare those values beyond which
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The Recommended Operating Conditionstable will define the conditions
for actual device operation.
Recommended Operating Conditions
Symbol
VCC
VIH
VIL
IOH
IOL
TA
Parameter
Supply Voltage
HIGH Level Input Voltage
LOW Level Input Voltage
HIGH Level Output Current
LOW Level Output Current
Free Air Operating Temperature
Min Nom
4.75 5
2
0
Electrical Characteristics
over recommended operating free air temperature (unless otherwise noted)
Symbol
Parameter
Conditions
Min
VI Input Clamp Voltage
VCC = Min, II = −18 mA
VOH HIGH Level
Output Voltage
VOL LOW Level
VCC = Min, IOH = Max
VIL = Max, VIH = Min
VCC = Min, IOL = Max
2.7
Output Voltage
II Input Current @ Max Input Voltage
IIH HIGH Level Input Current
IIL LOW Level Input Current
IOS Short Circuit Output Current
ICC Supply Current (DM74S138)
ICC Supply Current (DM74S139)
Note 2: All typicals are at VCC = 5V, TA = 25°C.
VIH = Min, VIL = Max
VCC = Max, VI = 5.5V
VCC = Max, VI = 2.7V
VCC = Max, VI = 0.5V
VCC = Max (Note 3)
VCC = Max (Note 4)
VCC = Max (Note 4)
40
Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 4: ICC is measured with all outputs enabled and OPEN.
Max
5.25
0.8
1
20
70
Units
V
V
V
mA
mA
°C
Typ
(Note 2)
3.4
49
60
Max
1.2
0.5
1
50
2
100
74
90
Units
V
V
V
mA
µA
mA
mA
mA
mA
3 www.fairchildsemi.com
Free Datasheet http://www.Datasheet4U.com










Скачать PDF:

[ 74S138.PDF Даташит ]

Номер в каталогеОписаниеПроизводители
74S13313-Input NAND GateSYC
SYC
74S13412-INPUT POSITIVE-NAND GATES WITH 3-STATE OUTPUTSFairchild
Fairchild
74S13412-INPUT POSITIVE-NAND GATES WITH 3-STATE OUTPUTSSignetics
Signetics
74S135Quad Exclusive OR/NOR GateFairchild
Fairchild

Номер в каталоге Описание Производители
TL431

100 мА, регулируемый прецизионный шунтирующий регулятор

Unisonic Technologies
Unisonic Technologies
IRF840

8 А, 500 В, N-канальный МОП-транзистор

Vishay
Vishay
LM317

Линейный стабилизатор напряжения, 1,5 А

STMicroelectronics
STMicroelectronics

DataSheet26.com    |    2020    |

  Контакты    |    Поиск