SN74ALS654屬于集成電路（IC）的緩沖器驅(qū)動器接收器收發(fā)器。由美國德州儀器公司制造生產(chǎn)的SN74ALS654緩沖器，驅(qū)動器，接收器，收發(fā)器邏輯緩沖器、驅(qū)動器、接收器和收發(fā)器允許隔離對某個電路的邏輯信號的訪問，以用于另一電路。緩沖器將其輸入信號（不變或反相）傳遞到其輸出，并可能用于清除弱信號或驅(qū)動負載。在布爾邏輯仿真器中，緩沖器主要用于增加傳播延遲。邏輯接收器和收發(fā)器允許在數(shù)據(jù)總線之間進行隔離通信。

Bus Transceivers/Registers

Independent Registers and Enables for A

and B Buses

Multiplexed Real-Time and Stored Data

Choice of True or Inverting Data Paths

Choice of 3-State or Open-Collector

Outputs to A Bus

description

These devices consist of bus-transceiver 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-enable (OEAB and OEBA) inputs are

provided to control the transceiver functions.

Select-control (SAB and SBA) inputs are provided

to select real-time or stored data transfer. The

circuitry used for select control eliminates 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 input level selects stored data. Figure 1

illustrates 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-type flip-flops by low-to-high transitions at

the appropriate clock (CLKAB or CLKBA) terminals, regardless of the select- or output-control terminals. When

SAB and SBA are in the real-time transfer mode, it is possible to store data without using the internal D-type

flip-flops by simultaneously enabling OEAB and OEBA. In this configuration, each output reinforces its input.

When all other data sources to the two sets of bus lines are at high impedance, each set of bus lines remains

at its last state.

The -1 versions of the SN74ALS651A and SN74ALS652A are identical to the standard versions except that the

recommended maximum IOL for the -1 versions is increased to 48 mA. There are no -1 versions of the

SN54ALS652, SN54ALS653, SN74ALS653, and SN74ALS654.