Product details

Supply voltage (min) (V) 4.5 Supply voltage (max) (V) 5.5 Number of channels 8 IOL (max) (mA) 24 IOH (max) (mA) -24 Input type TTL Output type CMOS Features Balanced outputs, Positive input clamp diode, Very high speed (tpd 5-10ns) Technology family ACT Rating Catalog Operating temperature range (°C) -55 to 125
Supply voltage (min) (V) 4.5 Supply voltage (max) (V) 5.5 Number of channels 8 IOL (max) (mA) 24 IOH (max) (mA) -24 Input type TTL Output type CMOS Features Balanced outputs, Positive input clamp diode, Very high speed (tpd 5-10ns) Technology family ACT Rating Catalog Operating temperature range (°C) -55 to 125
SOIC (DW) 24 159.65 mm² 15.5 x 10.3
  • Buffered inputs
  • Typical propagation delay:
    5.3 ns @ VCC = 5 V, TA = 25°C, CL = 50pF
  • Exceeds 2-kV 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 1.5-V to 5.5-V operation and balanced noise immunity at 30% of the supply
  • ± 24-mA output drive current
    - Fanout to 15 FAST* ICs
    - Drives 50-ohm transmission lines
  • Characterized for operation from –40° to 85°C

*FAST is a Registered Trademark of Fairchild Semiconductor Corp.

  • Buffered inputs
  • Typical propagation delay:
    5.3 ns @ VCC = 5 V, TA = 25°C, CL = 50pF
  • Exceeds 2-kV 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 1.5-V to 5.5-V operation and balanced noise immunity at 30% of the supply
  • ± 24-mA output drive current
    - Fanout to 15 FAST* ICs
    - Drives 50-ohm transmission lines
  • Characterized for operation from –40° to 85°C

*FAST is a Registered Trademark of Fairchild Semiconductor Corp.

The RCA CD54/74AC646 and CD54/74AC648 and the CD54/74ACT646 and CD54/74ACT648 3-state, octal-bus transceiver/registers use the RCA ADVANCED CMOS technology. The CD54/74AC648 and CD54/74ACT648 have inverting outputs. The CD54/74AC646 and CD54/74ACT646 have non-inverting outputs. These devices are bus transceivers with D-type flip-flops which act as internal storage registers on the LOW-to-HIGH transition of either CAB or CBA clock inputs. Output Enable (OE\) and Direction (DIR) inputs control the transceiver functions. Data present at the high-impedance output can be stored in either register or both but only one of the two buses can be enabled as outputs at any one time. The Select controls (SAB and SBA) can multiplex stored and transparent (real time) data. The Direction control determines which data bus will receive data when the Output Enable (OE\) is LOW. In the high-impednace mode (Output Enable HIGH), A data can be stored in one register and B data can be stored in the other register. The clocks are not gated with the Direction (DIR) and Output Enable (OE\) terminals; data at the A or B terminals can be clocked into the storage flip-flops at any time.

The CD74AC/ACT646 and CD74AC/ACT648 are supplied in 24-lead dual-in-line narrow-body plastic packages (EN suffix) and in 24-lead dual-in-line small-outline plastic packages (M suffix). Both package types are operable over the following temperature ranges: Commercial (0 to 70°C); Industrial (-40 to +85°C); and Extended Industrial/Military (-55 to +125°C).

The CD54/ACT646 and CD54AC/ACT648, available in chip form (H suffix), are operable over the -55 to +125°C temperature range.

The RCA CD54/74AC646 and CD54/74AC648 and the CD54/74ACT646 and CD54/74ACT648 3-state, octal-bus transceiver/registers use the RCA ADVANCED CMOS technology. The CD54/74AC648 and CD54/74ACT648 have inverting outputs. The CD54/74AC646 and CD54/74ACT646 have non-inverting outputs. These devices are bus transceivers with D-type flip-flops which act as internal storage registers on the LOW-to-HIGH transition of either CAB or CBA clock inputs. Output Enable (OE\) and Direction (DIR) inputs control the transceiver functions. Data present at the high-impedance output can be stored in either register or both but only one of the two buses can be enabled as outputs at any one time. The Select controls (SAB and SBA) can multiplex stored and transparent (real time) data. The Direction control determines which data bus will receive data when the Output Enable (OE\) is LOW. In the high-impednace mode (Output Enable HIGH), A data can be stored in one register and B data can be stored in the other register. The clocks are not gated with the Direction (DIR) and Output Enable (OE\) terminals; data at the A or B terminals can be clocked into the storage flip-flops at any time.

The CD74AC/ACT646 and CD74AC/ACT648 are supplied in 24-lead dual-in-line narrow-body plastic packages (EN suffix) and in 24-lead dual-in-line small-outline plastic packages (M suffix). Both package types are operable over the following temperature ranges: Commercial (0 to 70°C); Industrial (-40 to +85°C); and Extended Industrial/Military (-55 to +125°C).

The CD54/ACT646 and CD54AC/ACT648, available in chip form (H suffix), are operable over the -55 to +125°C temperature range.

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Technical documentation

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Type Title Date
* Data sheet Octal-Bus Transceiver/Registers, 3-State datasheet 03 Dec 1998
Application note Implications of Slow or Floating CMOS Inputs (Rev. E) 26 Jul 2021
Selection guide Logic Guide (Rev. AB) 12 Jun 2017
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) 02 Dec 2015
User guide LOGIC Pocket Data Book (Rev. B) 16 Jan 2007
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection 08 Jul 2004
Application note Selecting the Right Level Translation Solution (Rev. A) 22 Jun 2004
Application note TI IBIS File Creation, Validation, and Distribution Processes 29 Aug 2002
Application note CMOS Power Consumption and CPD Calculation (Rev. B) 01 Jun 1997
Application note Designing With Logic (Rev. C) 01 Jun 1997
Application note Using High Speed CMOS and Advanced CMOS in Systems With Multiple Vcc 01 Apr 1996

Design & development

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Evaluation board

14-24-LOGIC-EVM — Logic product generic evaluation module for 14-pin to 24-pin D, DB, DGV, DW, DYY, NS and PW packages

The 14-24-LOGIC-EVM evaluation module (EVM) is designed to support any logic device that is in a 14-pin to 24-pin D, DW, DB, NS, PW, DYY or DGV package,

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SOIC (DW) 24 View options

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