CD74HC138集成电路（IC）的信号开关多路复用器解码器规格书PDF中文资料

CD74HC138属于集成电路（IC）的信号开关多路复用器解码器。由美国德州仪器公司制造生产的CD74HC138信号开关，多路复用器，解码器逻辑型信号开关、多路复用器和编码器 IC 可用于对以数字格式表示数据的电信号进行路由和选择。这些器件与设计用于模拟信号的类似产品有所不同，它们保留的信息表示为两个电状态之一，而不是两个外部界限内的无穷变化量。

Qualified for Automotive Applications

Select One of Eight Data Outputs Active

Low

I/O Port or Memory Selector

Three Enable Inputs to Simplify Cascading

Typical Propagation Delay of 13 ns at

VCC = 5 V, CL = 15 pF, TA = 25
C

Fanout (Over Temperature Range)

− Standard Outputs . . . 10 LSTTL Loads

− Bus Driver Outputs . . . 15 LSTTL Loads

Balanced Propagation Delay and Transition

Times

Significant Power Reduction Compared to

LSTTL Logic ICs

2-V to 6-V VCC Operation

High Noise Immunity; NIL or NIH = 30% of

VCC, VCC = 5 V

description/ordering information

The CD74HC138 is a high-speed silicon-gate CMOS

decoder well suited to memory address decoding or

data routing applications. This circuit features low

power consumption usually associated with CMOS circuitry, yet has speeds comparable to low-power Schottky

TTL logic. The circuit has three binary select inputs (A0, A1, and A2). If the device is enabled, these inputs

determine which one of the eight normally high outputs of the HC138 will go low.

Two active-low and one active-high enables (E1, E2, and E3) are provided to ease the cascading of decoders.

The decoder’s eight outputs can drive ten low-power Schottky TTL equivalent loads.