Single-Rail Outputs on ‘LS399

Selects One of Two 4-Bit Data Sources and

Stores Data Synchronously with System

Clock

Applications:

Dual Source for Operands and Constants

in Arithmetic Processor; Can Release

Processor Register Files for Acquiring

New Data

Implement Separate Registers Capable of

Parallel Exchange of Contents Yet Retain

External Load Capability

Universal Type Register for Implementing

Various Shift Patterns: Even Has

Compound Left-Right Capabilities

description

This monolithic quadruple two-input multiplexer with

storage provides essentially the equivalent functional

capabilities of two separate MSI functions

(SNB4LS157/SN74LS157 and SN54LS175/

SN74LS175) in a single 16-pin package.

When the word-select input is low, word 1 (A1, B1,

C1, D1) is applied to the flip-flops. A high input to

word select will cause the selection of word 2 (A2,

B2, C2, D2). The selected word is clocked to the

output terminals on the positive-going edge of the

clock pulse.

Typical power dissipation is 37 milliwatts. The

SN54LS399 is characterized for operation over the full

military range of —55°C to 125°C. The SN74LS399

is characterized for operation from 0°C to 70°C.