ON Semiconductor MC74AC646 Octal Transceiver and Register

The MC74AC646 is an integrated circuit product from ON Semiconductor, designed to provide a versatile interface between a bus and the system's memory, microprocessor, or peripheral devices. This IC is part of the high-speed CMOS range and is particularly notable for its octal bidirectional transceiver and register functionality, which makes it an ideal choice for a wide range of digital communication and processing tasks.

The device consists of eight non-inverting bidirectional buffers with 3-state outputs and is designed to be used as either a bus transceiver or a buffer/memory device. With two distinct sections, each containing four bidirectional transceivers, the MC74AC646 ensures that data can flow smoothly in both directions between ports, providing a high degree of flexibility for various circuit designs.

Key features of the MC74AC646 include:

• A bus-hold feature on the data inputs, eliminating the need for external pull-up or pull-down resistors.
• Separate control logic for each section of the device.
• Output enable (OE) and direction (DIR) pins for easy control of data flow.
• Compatibility with TTL levels, allowing for easy integration into existing systems that use TTL logic.
• Operation from a 2V to 6V power supply, providing versatility in different power environments.
• High noise immunity characteristic of CMOS devices.

The MC74AC646 operates at high speeds, with a typical t_pd (propagation delay time) of 8 ns when powered by a 5V supply. This makes it suitable for high-speed data transmission and processing applications where minimal delay is crucial. Additionally, the device's low power consumption makes it an energy-efficient choice for battery-operated devices.

ON Semiconductor ensures that the MC74AC646 is manufactured to high standards, providing reliable performance across its specified operating temperature range. This product is commonly available in a 24-lead plastic SOIC package, making it easy to integrate into a variety of PCB designs. Whether used in microprocessor expansion, memory interfacing, or as an input/output port, the MC74AC646 provides a high-performance solution that designers can trust.