The HD74ACT244P is an octal buffer/line driver with three-state outputs manufactured by Hitachi. This device is part of the Advanced CMOS Technology (ACT) logic family, offering improved speed and performance compared to standard CMOS logic. It's designed to drive heavily loaded buses and transmission lines while providing minimal signal degradation.

Applications

• Memory Interfacing: Used as a buffer between memory devices and the system bus.
• Address Decoding: Employed in address decoding circuits to drive multiple memory chips or peripherals.
• Data Bus Driving: Utilized to increase the drive capability of data buses.
• Line Driving: Used to transmit signals over longer distances with minimal signal degradation.

Features

• Octal Buffer/Line Driver: Contains eight independent buffers/line drivers in a single package.
• Three-State Outputs: Offers three output states: HIGH, LOW, and HIGH-impedance (disabled).
• High Output Drive Capability: Provides sufficient output current to drive heavily loaded buses.
• Low Input Current: Requires minimal input current, reducing the load on the driving circuit.
• Fast Propagation Delay: Offers fast propagation delay times, enabling high-speed data transfer.

Benefits

• Increased Bus Drive: Enhances the drive capability of buses, allowing them to support more devices.
• Improved Signal Integrity: Minimizes signal degradation and noise on buses.
• Reduced Loading Effects: Reduces the loading effects on the driving circuit.
• Flexible Bus Management: Three-state outputs allow for selective enabling and disabling of bus devices.
• High-Speed Data Transfer: Fast propagation delay enables high-speed data transfer on buses.

Additional Details

The HD74ACT244P is typically available in a DIP (Dual In-line Package) suitable for through-hole mounting. Key specifications include a propagation delay of approximately 5-10 ns, an output drive current of around 24 mA, and an operating temperature range of -40°C to +85°C. The three-state outputs are controlled by two enable inputs. When an enable input is high, all the outputs associated with that enable input are placed in a high-impedance state, effectively disconnecting them from the bus.