The 54FCT138/LMQB/QS is a 1-of-8 Decoder/Demultiplexer manufactured by National Semiconductor (now Texas Instruments). It belongs to the 54FCT family of high-speed, low-power CMOS logic devices. The 'LMQB/QS' suffix denotes the package type and quality screening level, often associated with military or high-reliability applications.

Applications

• Memory address decoding
• Chip selection in memory systems
• Data routing in communication systems
• Address decoding in peripheral controllers
• Instrumentation and control systems

Features

• 1-of-8 decoding capability
• High-speed operation
• Low power consumption
• Three enable inputs for device control
• Active-low outputs
• Military temperature range

Benefits

• Efficient address decoding for memory and peripheral devices
• Fast switching speeds for high-performance systems
• Reduced power consumption for energy-efficient designs
• Flexible device control through enable inputs
• Simplified interface with active-low logic systems

Additional Details

The 54FCT138/LMQB/QS decodes a 3-bit binary address applied to its inputs and activates one of its eight outputs, providing a 1-of-8 selection. The device's operation is controlled by three enable inputs, allowing for cascading and expansion. The active-low outputs simplify interface with other logic devices. The device operates from a 5V power supply. Key electrical characteristics, including propagation delays, input and output voltage levels, and power consumption, are specified in the National Semiconductor (TI) datasheet. The military-grade designation ensures that the device has undergone rigorous testing and screening to meet stringent reliability requirements. The specific package indicated by 'LMQB/QS' (consult the datasheet for precise details) affects mounting and assembly procedures. It finds extensive application in systems requiring the selection of one of several memory locations or peripheral devices.