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DM74LS157 • DM74LS158 Quad 2-Line to 1-Line Data Selectors/Multiplexers

September 1986 Revised April 2000

DM74LS157 • DM74LS158 Quad 2-Line to 1-Line Data Selectors/Multiplexers
General Description
These data selectors/multiplexers contain inverters and drivers to supply full on-chip data selection to the four output gates. A separate strobe input is provided. A 4-bit word is selectedfrom one of two sources and is routed to the four outputs. The DM74LS157 presents true data whereas the DM74LS158 presents inverted data to minimize propagation delay time.

Applications
• Expand any data input point • Multiplex dual data buses • Generate four functions of two variables (one variable is common) • Source programmable counters

Features
s Buffered inputs and outputs s TypicalPropagation Time DM74LS157 DM74LS158 DM74LS157 DM74LS158 9 ns 7 ns 49 mW 24 mW

s Typical Power Dissipation

Ordering Code:
Order Number DM74LS157M DM74LS157SJ DM74LS157N DM74LS158M DM74LS158N Package Number M16A M16D N16E M16A N16E Package Description 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow 16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide 16-LeadPlastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.

Connection Diagrams
DM74LS157 DM74LS158

© 2000 Fairchild SemiconductorCorporation

DS006396

www.fairchildsemi.com

DM74LS157 • DM74LS158

Function Table
Inputs Strobe H L L L L
H = HIGH Level L = LOW Level X = Don’t Care

Output Y A X L H X X B X X X L H DM74LS157 DM74LS158 L L H L H H H L H L

Select X L L H H

Logic Diagrams
DM74LS157 DM74LS158

www.fairchildsemi.com

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DM74LS157 • DM74LS158

Absolute Maximum Ratings(Note 1)
SupplyVoltage Input Voltage Operating Free Air Temperature Range Storage Temperature Range 7V 7V 0°C to +70°C −65°C to +150°C
Note 1: The “Absolute Maximum Ratings” are 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 maximumratings. The “Recommended Operating Conditions” table will define the conditions for actual device operation.

DM74LS157 Recommended Operating Conditions
Symbol VCC VIH VIL IOH IOL TA Supply Voltage HIGH Level Input Voltage LOW Level Input Voltage HIGH Level Output Current LOW Level Output Current Free Air Operating Temperature 0 Parameter Min 4.75 2 0.8 −0.4 8 70 Nom 5 Max 5.25 Units V V V mA mA°C

DM74LS157 Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted) Symbol VI VOH VOL II IIH IIL IOS ICC Parameter Input Clamp Voltage HIGH Level Output Voltage LOW Level Output Voltage Input Current @ Max Input Voltage HIGH Level Input Current LOW Level Input Current Short Circuit Output Current Supply Current Conditions VCC = Min, II = −18 mAVCC = Min, IOH = Max, VIL = Max, VIH = Min VCC = Min, IOL = Max, VIL = Max, VIH = Min IOL = 4 mA, VCC = Min VCC = Max VI = 7V VCC = Max VI = 2.7V VCC = Max VI = 0.4V VCC = Max (Note 3) VCC = Max (Note 4) S or G A or B S or G A or B S or G A or B −20 9.7 2.7 3.4 0.35 0.25 0.5 0.4 0.2 0.1 40 20 −0.8 −0.4 −100 16 Min Typ (Note 2) Max −1.5 Units V V V mA µA mA mA mA

Note 2: All typicals are at VCC= 5V, TA = 25°C. 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 4.5V applied to all inputs and all outputs OPEN.

DM74LS157 Switching Characteristics
at VCC = 5V and TA = 25°C From (Input) Symbol Parameter To (Output) CL = 15 pF Min tPLH tPHL tPLH tPHL tPLH tPHL Propagation Delay Time LOW-to-HIGH Level...