Product details


Function Encoder, Multiplexer Technology Family AC VCC (Min) (V) 1.5 VCC (Max) (V) 5.5 Channels (#) 4 Voltage (Nom) (V) 1.5, 3.3, 5 F @ nom voltage (Max) (MHz) 100 ICC @ nom voltage (Max) (mA) 0.08 tpd @ nom Voltage (Max) (ns) 106, 11.8, 8.5 Configuration 2:1 Product type 3-State Output IOL (Max) (mA) 24 IOH (Max) (mA) -24 Rating Catalog Operating temperature range (C) -55 to 125 Bits (#) 2 Digital input leakage (Max) (uA) 5 ESD CDM (kV) 0.75 ESD HBM (kV) 2 open-in-new Find other Encoders & decoders

Package | Pins | Size

PDIP (N) 16 181 mm² 19.3 x 9.4 SOIC (D) 16 59 mm² 9.9 x 6 open-in-new Find other Encoders & decoders


  • ’AC257, ’ACT257. . . . . . . . . . . . . Non-Inverting Outputs
  • CD74ACT258 . . . . . . . . . . . . . . . . . . . Inverting Outputs
  • Buffered Inputs
  • Typical Propagation Delay
    - 4.4ns at VCC = 5V, TA = 25°C, CL = 50pF
  • Exceeds 2kV ESD Protection MIL-STD-883, Method 3015
  • SCR-Latchup-Resistant CMOS Process and Circuit Design
  • Speed of Bipolar FAST™/AS/S with Significantly Reduced Power Consumption
  • Balanced Propagation Delays
  • AC Types Feature 1.5V to 5.5V Operation and Balanced Noise Immunity at 30% of the Supply
  • ±24mA Output Drive Current
    - Fanout to 15 FAST™ ICs
    Drives 50 Transmission Lines
  • Characterized for operation from –40° to 85°C

FAST™ is a Trademark of Fairchild Semiconductor.

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The ’AC257, ’ACT257 and CD74ACT258 are quad 2-input multiplexers with three-state outputs that utilize Advanced CMOS Logic technology. Each of these devices selects four bits of data from two sources under the control of a common Select input (S). The Output Enable (OE\) is active LOW. When OE\ is HIGH, all of the outputs (Y or Y\) are in the high-impedance state regardless of all other input conditions.

Moving data from two groups of registers to four common output buses is a common use of the ’AC257, ’ACT257, and CD74ACT258. The state of the Select input determines the particular register from which the data comes. The ’AC257, ’ACT257 and CD74ACT258 can also be used as function generators.

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Technical documentation

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No results found. Please clear your search and try again. View all 14
Type Title Date
* Datasheet Quad 2-Input Multiplexer with Three-State Outputs datasheet (Rev. A) May 17, 2000
Selection guides Logic Guide (Rev. AB) Jun. 12, 2017
Application notes Implications of Slow or Floating CMOS Inputs (Rev. D) Jun. 23, 2016
Application notes Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) Dec. 02, 2015
More literature HiRel Unitrode Power Management Brochure Jul. 07, 2009
User guides LOGIC Pocket Data Book (Rev. B) Jan. 16, 2007
Application notes Semiconductor Packing Material Electrostatic Discharge (ESD) Protection Jul. 08, 2004
More literature Logic Cross-Reference (Rev. A) Oct. 07, 2003
Application notes TI IBIS File Creation, Validation, and Distribution Processes Aug. 29, 2002
Application notes CMOS Power Consumption and CPD Calculation (Rev. B) Jun. 01, 1997
Application notes Designing With Logic (Rev. C) Jun. 01, 1997
Application notes Input and Output Characteristics of Digital Integrated Circuits Oct. 01, 1996
Application notes Live Insertion Oct. 01, 1996
Application notes Using High Speed CMOS and Advanced CMOS in Systems With Multiple Vcc Apr. 01, 1996

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Hardware development

document-generic User guide
This EVM is designed to support any logic device that has a D, DW, DB, NS, PW, P, N, or DGV package in a 14 to 24 pin count.
  • Board design allows for versatility in evaluation
  • Supports a wide-range of logic devices

CAD/CAE symbols

Package Pins Download
PDIP (N) 16 View options
SOIC (D) 16 View options

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