DatasheetsPDF.com

DM74ALS257 Dataheets PDF



Part Number DM74ALS257
Manufacturers Fairchild Semiconductor
Logo Fairchild Semiconductor
Description 3-STATE Quad 1-of-2-Line Data Selector/Multiplexer
Datasheet DM74ALS257 DatasheetDM74ALS257 Datasheet (PDF)

DM74ALS257 • DM74ALS258 3-STATE Quad 1-of-2-Line Data Selector/Multiplexer April 1984 Revised February 2000 DM74ALS257 • DM74ALS258 3-STATE Quad 1-of-2-Line Data Selector/Multiplexer General Description These data selectors/multiplexers contain inverters and drivers to supply full on-chip data selection to the four 3STATE outputs that can interface directly with data lines of bus-organized systems. A 4-bit word selected from one of two sources is routed to the four outputs. The DM74ALS257 pres.

  DM74ALS257   DM74ALS257



Document
DM74ALS257 • DM74ALS258 3-STATE Quad 1-of-2-Line Data Selector/Multiplexer April 1984 Revised February 2000 DM74ALS257 • DM74ALS258 3-STATE Quad 1-of-2-Line Data Selector/Multiplexer General Description These data selectors/multiplexers contain inverters and drivers to supply full on-chip data selection to the four 3STATE outputs that can interface directly with data lines of bus-organized systems. A 4-bit word selected from one of two sources is routed to the four outputs. The DM74ALS257 presents true data whereas the DM74ALS258 presents inverted data to minimize propagation delay time. This 3-STATE output feature means that n-bit (paralleled) data selectors with up to 258 sources can be implemented for data buses. It also permits the use of standard TTL registers for data retention throughout the system. Features s Switching specifications at 50 pF s Switching specifications guaranteed over full temperature and VCC range s Advanced oxide-isolated, ion-implanted Schottky TTL process s Functionally and pin for pin compatible with Schottky and low power Schottky TTL counterpart s Improved AC performance over Schottky and low power Schottky counterparts s 3-STATE buffer-type outputs drive bus lines directly s Expand any data input point s Multiplex dual data buses s General four functions of two variables (one variable is common) s Source programmable counters Ordering Code: Order Number DM74ALS257M DM74ALS257SJ DM74ALS257N DM74ALS258M DM74ALS258N 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-Lead Plastic 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 Diagram Function Table Inputs Output Control H L L L L Select X L L H H A X L H X X B X X X L H Output Y DM74ALS257 DM74ALS258 Z L H L H Z H L H L H = HIGH Level L = LOW Level X = Don't Care Z = High Impedance (OFF) © 2000 Fairchild Semiconductor Corporation DS006227 www.fairchildsemi.com DM74ALS257 • DM74ALS258 Logic Diagrams DM74ALS257 DM74ALS258 www.fairchildsemi.com 2 DM74ALS257 • DM74ALS258 Absolute Maximum Ratings(Note 1) Supply Voltage Input Voltage Voltage Applied to Disabled Output Operating Free Air Temperature Range Storage Temperature Range Typical θJA N Package M Package 73.0°C/W 102.0°C/W 7V 7V 5.5V 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 maximum ratings. The “Recommended Operating Conditions” table will define the conditions for actual device operation. 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 4.5 2 0.8 −2.6 24 70 Nom 5 Max 5.5 Units V V V mA mA °C Electrical Characteristics over recommended operating free air temperature range. All typical values are measured at VCC = 5V, TA = 25°C. Symbol VIK VOH VOL II IIH IIL IO IOZH IOZL ICCH ICCL ICCZ Parameter Input Clamp Voltage HIGH Level Output Voltage LOW Level Output Voltage Input Current at Maximum Input Voltage HIGH Level Input Current LOW Level Input Current Output Drive Current OFF-State Output Current HIGH Level Voltage Applied OFF-State Output Current, LOW Level Voltage Applied Supply Current Supply Current Supply Current VCC = 5.5V, VIH = 7V VCC = 5.5V, VIH = 2.7V VCC = 5.5V, VIL = 0.4V VCC = 5.5V, VO = 2.25V VCC = 5.5V, VO = 2.7V VCC = 5.5V, VO = 0.4V Outputs HIGH Outputs LOW Outputs Disabled 3 2.5 8 7 9 8 DM74ALS257 VCC = 5.5V DM74ALS258 Outputs OPEN DM74ALS257 DM74ALS258 DM74ALS257 DM74ALS258 −30 VCC = 4.5V IOH = −0.4 mA VCC = 4.5V IOL = 12 mA IOL = 24 mA Conditions VCC = 4.5V, II = −18 mA IOH = −2.6 mA 2.4 VCC − 2 0.25 0.35 0.4 0.5 0.1 20 −0.1 −112 20 −20 6 4 12 11 14 13 3.3 Min Typ Max −1.5 Units V V V V V mA µA mA mA µA µA mA mA mA mA mA mA 3 www.fairchildsemi.com DM74ALS257 • DM74ALS258 Switching Characteristics DM74ALS257 over recommended operating free air temperature range Symbol tPLH tPHL tPLH tPHL tZH tZL tHZ tLZ Parameter Propagation Delay Time LOW-to-HIGH Level Output Propagation Delay Time HIGH-to-LOW Level Output Propagation Delay Time LOW-to-HIGH Level Output Propagation Delay Time HIGH-to-LOW Level Output Output Enable Time to HIGH Level Output Enable Time to LOW Level Output Disable Time from HIGH Level Output Disable Time from LOW Level Conditions VCC = 4.5V to 5.5V CL = 50 pF RL = 500Ω From Data D.


DM74ALS253 DM74ALS257 DM74ALS27


@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site.
(Privacy Policy & Contact)