CD74ACT652 - Octal Non-Inverting Bus Transceivers/Registers with 3-State Outputs

The RCA CD54/74AC651 and CD54/74AC652 and the CD54/74ACT651 and CD54/74ACT652 3-state, octal-bus transceiver/registers use the RCA ADVANCED CMOS technology. The CD54/74AC651 and CD54/74ACT651 have inverting outputs. The CD54/74AC562 and CD54/74ACT652 have non-inverting outputs. These devices consist of bus tranceiver circuits, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the data bus or from the internal storage registers. Output Enables OE_AB and OE\_BA are provided to control the transceiver functions. SAB and SBA control pins are provided to select whether real-time or stored data is transferred. The circuitry used for select control will eliminate the typical decoding glitch that occurs in a multiplexer during the transition between stored and real-time data. A LOW input level selects real-time data, and a HIGH selects stored data. The following examples demonstrate the four fundamental bus-management functions that can be performed with the octal-bus transceivers and registers.

Data on the A or B data bus, or both, can be stored in the internal D flip-flops by low-to-high transitions at the appropriate clock pins (CAB or CBA) regardless of the select or enable control pins. When SAB and SBA are in the real-time transfer mode, it is also possible to store data without using the internal D-type flip-flops by simultaneously enabling OE_AB and OE\_BA. In this configuration, each output reinforces its input. Thus, when all other data sources to the two sets of bus lines are a high impedance, each set of bus lines will remain at its last state.

The CD74AC/ACT651 and CD74AC/ACT652 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 ty0es are operable over the following temperature ranges. Commerical (0 to 70°C); industrial (-40 to +85°C); and Extended Industrial/Military (-55 to +125°C).

The CD54AC/ACT651 and CD54AC/ACT652, available in chip form (H suffix), are operable over the -55 to +125°C temperature range.

Products containing the "CD74ACT652" keyword are: CD74ACT652EN , CD74ACT652M , CD74ACT652M , CD74ACT652M96 , CD74ACT652M96 , CD74ACT652M96G4 , CD74ACT652M96G4 (PB) , CD74ACT652MG4

• Buffered inputs
• Typical propagation delay:
  • 5.3 ns @ V_CC = 5 V, T_A = 25°C, C_L = 50 pF
• 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 of 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.