器件名称: SL74HC138
功能描述: 1-of-8 Decoder/Demultiplexer
文件大小: 51.55KB 共5页
简 介:SL74HC138
1-of-8 Decoder/Demultiplexer
High-Performance Silicon-Gate CMOS
The SL74HC138 is identical in pinout to the LS/ALS138. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALSTTL outputs. The SL74HC138 decodes a three-bit Address to one-of-eight activelow outputs. This device features three Chip Select inputs, two activelow 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. Outputs Directly Interface to CMOS, NMOS, and TTL Operating Voltage Range: 2.0 to 6.0 V Low Input Current: 1.0 A High Noise Immunity Characteristic of CMOS Devices
ORDERING INFORMATION SL74HC138N Plastic SL74HC138D SOIC TA = -55° to 125° C for all packages
PIN ASSIGNMENT
LOGIC DIAGRAM
FUNCTION TABLE
Inputs CS1 CS2 CS3 X X H X H X L X X H H H H H H H H L L L L L L L L L L L L L L L L A2 A1 A0 X X X X X X X X X LL L L L H L H L L H H H L L H L H H H L H H H Outputs Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 H H H H H H H H H H H H H H H H H H H H H H H H L H H H H H H H H L H H H H H H H H L H H H H H H H H L H H H H H H H H H H H H H H H H H H H H
PIN 16 =VCC PIN 8 = GND
L H H H H L H H H H L H H H H L
H = high level (steady state) L = low level (steady state) X = don’t care
SLS
System ……
