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54LS157-3

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£ 5 | National

J u ś Sem iconductor

54 LS157/DM54LS157/DM74LS157, 54LS158/DM54LS158/DM74LS158

Quad 2-Line to 1-Line Data Selectors/Multiplexers

General Description

These data selectors/mu!tiplexers contain irwerters and drivers to supply fuli on-chip data selection to the four out- put gates. A separate strobe input is provided. A 4-bit word is selected from one of two sources and is routed to the four outputs. The LS157 presents true data whereas the LS158 presents inverted data to minimize propagation delay time.

Applications

■ Expand any data input point

■ Muitiplex dual data buses

■ Generale four functions of two variables (one variable is common)

■ Source programmable counters

Features

d Buffered inputs and outputs 0 Typical Propagation Time

LS157 9 ns LS158 7 ns

m Typical Power Dissipation LS157 49 mW LS158 24 mW

0 Alternate Military/Aerospace device (54LS157, 54LS158) is available. Contact a National Semiconduc­

tor Sales Office/Distributor for specifications.

Connection Diagrams

STROBE

VCC G A4

Dual-ln-Line Package

INPUTS OUTPUT B4 Y4 ’ A3

IHPUTS OUTPUT B3 Y3

Dual-ln-Line Package

__ _____ INPUTS A l l ł r B l ł INPUTS

STROBE ^ OUTPUT

Vq c G A4 B4 Y4 A3

OUTPUT B3 Y3

TL/F/6396-1 T L /F /6396-2

Order Number 54LS157DMOB, 54LS157FMOB, 54LS157LMOB, DM54LS157J, DM54LS157W,

DM74LS157M or DM74LS157N See NS Package Number E20A, J16A,

M16A, N16E or W16A

Order Number 54LS158DMOB, 54LS158FMOB, 54LS158LMOB, DM54LS158J, DM54LS158W,

DM74LS158M o r DM74LS158N See NS Package Number E20A, J16A,

M16A, N16E or W16A

Function Table

Inputs O utputY

Strobe Select A B LS157 LS158

H X X X L H

L L L X L H

L L H X H L

L H X L L H

L H X H H L

H = High Level, L = Low Level, X = Don’t Care

2-171

L S 1 5 7 *L S 1 5 8

(2)

LS157*LS158

Absolute Maximum Ratings

(Notę)

If Mllltary/Aerospace specified devices are required, please contact the National Semiconductor Sales O ffice/Distri bu tors fo r avaiiability and specifications.

Supply Voltage 7V

Input Voltage 7 V

Operating Free Air Temperaturo Rangę

DM54LS and 54LS -5 5 °C to + 125°C

DM74LS 0°C to + 70°C

Storage T emperature Rangę - 65°C to + 150°C

Notę: The “Absolute Maximum Ratings” are those va/ues beyond which the safety o f the device cannot be guaran- teed. The device should not be operated a t these limits. The parametric va/ues definedin the “Electrical Characteristics”

table are not guaranteed a t the absolute maximum ratings.

The “Recommended Operating Conditions” table w illdefine the conditions for actual device operation.

Recommended Operating Conditions

Symbol Parameter DM54LS157 DM74LS157

Units

Min Nom Max Min Nom Max

Vcc Supply Voltage 4.5 5 5.5 4.75 5 5.25 V

V|H High Level Input Voltage 2 2 V

V|L Low Level Input Voltage 0.7 0.8 V

o h High Level Output Current -0 .4 - 0 .4 mA

•OL Low Level Output Current 4 8 mA

Ta Free Air Operating Temperaturo - 5 5 125 0 70 °C

’LS157 Electrical Characteristics

over recommended operating free air temperaturę rangę (unless otherwise noted)

Symbol Parameter Conditions Min Typ

(Notę 1) Max Units

V| Input Clamp Voltage Vcc = Min, l| = - 1 8 mA -1 .5 V

VoH High Level Output Vcc = Min, Io h = Max DM54 2.5 3.4 Voltage V||_ = Max, V |h = Min DM74 2.7 3.4 v

VoL Low Level Output Vcc Min, Io l = Max DM54 0.25 0.4

Voltage V|i_ = Max, Vm = Min DM74 0.35 0.5 V

Io l = 4 mA, Vq c = Min DM74 0.25 0.4

•l Input Current @ Max Vcc = Max S or G 0.2

Input Voltage V| = 7V A o r B 0.1 mA

•lH High Level Input Vcc = Max S or G 40

Current V| = 2.7V A or B 20 jaA

•lL Low Level Input Vcc = Max S or G -0 .8

Current V| = 0.4V A or B -0 .4 mA

•os Short Circuit Vcc = Max DM54 - 2 0 -1 0 0

Output Current (Notę 2) DM74 - 2 0 -1 0 0 mA

•cc Supply Current VCc = Max (Notę 3) 9.7 16 mA

Notę 1: A li typicals are at V < x = 5V, TA = 25#C.

Notę 2: Not morę than one output should be shorted at a time, and the duration should not exceed one second.

Notę 3: lec is measured with 4.5V applied to all inputs and all outputs open.

2-172

(3)

’LS157 Switching Characteristics

at Vcc = 5V and Ta = 25°C (See Section 1 for Test Waveforms and Output Load) From (Input)

To (Output)

r l = 2 k il

Symbol Parameter c L = 15 pF cL =50 pF Units

Min Max Min Max

tpLH Propagation Delay Time Low to High Level Output

Data

toY 14 18 ns

tpHL Propagation Delay Time High to Low Level Output

Data

toY 14 23 ns

*PLH Propagation Delay Time Low to High Level Output

Strobę

toY 20 24 ns

tpHL Propagation Delay Time High to Low Level Output

Strobę

toY 21 30 ns

tpLH Propagation Delay Time Low to High Level Output

Select

toY 23 28 ns

tpHL Propagation Delay Time High to Low Level Output

Select

toY 27 32 ns

Recommended Operating Conditions

’LS158 Electrical Characteristics

over recommended operating free air temperaturę rangę (unless otherwise noted)

Symbol Parameter Conditions Min Typ

(Notę 1) Max Units

V| Input Clamp Voltage Vcc — Min. I| = - 1 8 mA -1 .5 V

v OH High Level Output Voltage

Vcc = Min. Ioh = Max V|i_ = Max, Vm = Min

DM54 2.5 3.4

V

DM74 2.7 3.4

VOL Low Leve! Output Voltage

Vcc = Min, Iol = Max V||_ = Max, V|h = Min

DM54 0.25 0.4

V

DM74 0.35 0.5

Iql = 4 mA, Vcc = Min DM74 0.25 0.4

l| Input Current @ Max Input Voltage

<ds>u ^oII S or G 0.2

mA

A o r B 0.1

llH High Level Input Current

XŚ >r^- II ™oII o_>> S or G 40

jllA

A o r B 20

IlL Low Level Input Current

!>II ooII o_>> Sor G -0 .8

mA

A or B -0 .4

los Short Circuit Output Current

Vcc = Max (Notę 2)

DM54 - 2 0 -1 0 0

mA

DM74 - 2 0 -1 0 0

•cc Supply Current Vcc = Max (Notę 3) 4.8 8 mA

Notę 1: Ali typicals are at VCc = 5V, TA = 25°C.

Noto 2: Not morę than one output should be shorted at a time, and the duration should not exceed one second.

Notę 3: lec is measured with 4.5V applied to all inputs and all outputs open.

2-173

LS157*LS158

(4)

LS157*LS158

Symbol Parameter

From (Input) To (Output)

RL = 2 kn

Units CL = 15 pF CL = 50 pF

Min Max Min Max

tPLH Propagation Delay Time Low to High Level Output

Data

toY 12 18 ns

tPHL Propagation Delay Time High to Low Level Output

Data

toY 12 21 ns

tPLH Propagation Dełay Time Low to High Level Output

Strobę

toY 17 23 ns

tPHL Propagation Delay Time High to Low Level Output

Strobę

to Y 18 28 ns

*PLH Propagation Delay Time Low to High Level Output

Select

to Y 20 24 ns

tPHL Propagation Delay Time High to Low Level Output

Select

toY 24 36 ns

’LS158 Switching Characteristics

at Vcc = 5V and Ta = 25°C (See Section 1 for Test Waveforms and Output Load)

Logic Diagrams

LS157 LS158

, (2)

A4

B4

SELECT STROBĘ

TL/F/6396-3 T L /F /6396-4

2-174

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