| 品牌：APC | 型号：74HC138PW | 功率：36w |
September19932
Philips SemiconductorsProduct speci铿乧ation
3-to-8 line decoder/demultiplexer; inverting
74HC/HCT138
FEATURES
鈥emultiplexing capability
鈥ultiple input enable for easy expansion鈥deal for memory chip select decoding鈥ctive LOW mutually exclusive outputs鈥utput capability: standard鈥CCcategory: MSIGENERAL DESCRIPTION
The 74HC/HCT138 are high-speed Si-gate CMOS devicesand are pin compatible with low power Schottky TTL(LSTTL). They are specified in compliance with JEDECstandard no. 7A.
The 74HC/HCT138 decoders accept three binary
weighted address inputs (A0, A1, A2) and when enabled,provide 8 mutually exclusive active LOW outputs (Y0toY7).
The 鈥�138鈥� features three enable inputs: two active LOW(E1andE2) and one active HIGH (E3). Every output will beHIGH unlessE1andE2are LOW and E3is HIGH.This multiple enable function allows easy parallel
expansion of the 鈥�138鈥� to a 1-of-32 (5 lines to 32 lines)decoder with just four 鈥�138鈥� ICs and one inverter.The 鈥�138鈥� can be used as an eight output demultiplexer byusing one of the active LOW enable inputs as the datainput and the remaining enable inputs as strobes. Unusedenable inputs must be permanently tied to theirappropriate active HIGH or LOW state.
The 鈥�138鈥� is identical to the 鈥�238鈥� but has inverting outputs
