描述 Description

The MC74HCT138A is identical in pinout to the LS138. The HCT138A may be used as a level converter for interfacing TTL or NMOS outputs to High Speed CMOS inputs. The HCT138A decodes a three bit Address to one of eight active lot outputs. This device features three Chip Select inputs, two active low and one active high to facilitate the demultiplexing, cascading, and chip selecting functions. The demultiplexing function is accomplished by using the Address inputs to select the desired device output; one of the Chip Selects is used as a data input while the other Chip Selects are held in their active states.

特性 Features

? Chip Complexity: 122 FETs or 30.5 Equivalent Gates
? Output Drive Capability: 10 LSTTL Loads
? TTL/NMOS Compatible Input Levels
? Operating Voltage Range: 4.5 to 5.5 V
? Low Input Current: 1.0 μA
? Outputs Directly Interface to CMOS, NMOS, and TTL
? In Compliance with the Requirements Defined by JEDEC Standard No. 7A
? Pb-Free Packages are Available*

簡介

MC74HCT138A屬于集成電路（IC）的信號開關(guān)多路復(fù)用器解碼器。由制造生產(chǎn)的MC74HCT138A信號開關(guān)，多路復(fù)用器，解碼器邏輯型信號開關(guān)、多路復(fù)用器和編碼器 IC 可用于對以數(shù)字格式表示數(shù)據(jù)的電信號進行路由和選擇。這些器件與設(shè)計用于模擬信號的類似產(chǎn)品有所不同，它們保留的信息表示為兩個電狀態(tài)之一，而不是兩個外部界限內(nèi)的無窮變化量。