ON Semiconductor MC74AC138DR2 Decoder/Demultiplexer

The ON Semiconductor MC74AC138DR2 is a high-performance, 3-to-8 line decoder/demultiplexer integrated circuit, designed to address the needs of high-speed digital systems. This component is part of the AC series, renowned for its significant speed improvements over the older HC series, making it a suitable choice for modern digital applications that demand quick switching and reliable operation.

The device features three binary select inputs (A0, A1, and A2), an enable input (E1), and two active-low enable inputs (E2a, E2b). When the enable conditions are satisfied, the MC74AC138DR2 effectively decodes the select inputs to drive one of the eight mutually exclusive outputs low. This efficient decoding is ideal for memory chip selection, data routing, and resource allocation in complex digital systems.

The MC74AC138DR2 comes in a compact SOIC-16 package, which is both space-saving and suitable for automated surface-mount assembly processes. The small footprint of this package allows for a more efficient use of the printed circuit board (PCB) space, which is particularly valuable in densely packed electronic designs.

Key features of the MC74AC138DR2 include:

• Operating Voltage Range: 2V to 6V
• High-Speed: t<sub>PD = 4.5ns (Typ) at V<sub>CC = 5V
• Low Power Dissipation: I<sub>CC = 4μA (Max) at T<sub>A = 25°C
• Demultiplexing Capability
• Multiple Input Enable for Easy Expansion
• Active Low Mutually Exclusive Outputs
• Standard Pin Configuration
• Industrial Operating Temperature Range: -40°C to +85°C

The MC74AC138DR2's high-drive outputs and fast propagation delay times make it an excellent choice for interfacing with high-speed microprocessors, and its low power consumption is beneficial for portable and low-power applications. Its robust design ensures reliable operation even in harsh industrial environments.

Whether used in data multiplexing, memory address decoding, or as a control signal generator, the ON Semiconductor MC74AC138DR2 offers a combination of speed, efficiency, and versatility, making it a valuable component in the design of complex electronic systems.