MC74ACT245MG

Overview

The MC74ACT245MG is an octal bidirectional transceiver with three-state outputs manufactured by onsemi. It operates within a supply voltage range of 4.5 V to 5.5 V and supports an ambient temperature range from -40°C to +85°C. The device features eight non-inverting buffers with TTL-compatible inputs, providing high current sinking capability of 24 mA at both A and B ports. Propagation delay is typically 4.0 ns at 5.0 V with a 50 pF load.

Feature Summary

• Non-inverting buffer design ensures consistent data transmission without logical inversion
• Bidirectional data path allows flexible flow between port A and port B based on control signals
• TTL-compatible inputs enable direct interfacing with standard TTL logic devices

Applications

• Bus-oriented applications requiring bidirectional data transfer
• Memory bus architectures utilizing three-state output buffering
• Digital signal routing in systems with mixed TTL and CMOS logic levels

Procurement Notes

Verify the specific package suffix for the MG designation against official ordering information, as datasheets primarily list DW (SOIC-20) and DT (TSSOP-20) suffixes. Confirm RoHS compliance status and lead-free marking requirements directly with the manufacturer or authorized distributors prior to procurement.

Selection Notes

Select this component when TTL-compatible input thresholds are required alongside high drive strength. Ensure the application voltage remains strictly within the 4.5 V to 5.5 V range to maintain specified AC characteristics. Verify that the thermal resistance and power dissipation limits accommodate the system's operating environment.

Part Context

This part belongs to the MC74AC/ACT245 family of octal bidirectional transceivers. It shares functional similarities with other members like MC74ACT245DWG but differs in physical packaging. The ACT series specifically denotes TTL-compatible inputs, distinguishing it from the standard AC series which utilizes CMOS-compatible thresholds.

Replacement Considerations

MC74ACT245DWG

FAQ

How does the Transmit/Receive input determine data direction?

When the T/R input is HIGH, data flows from the A ports to the B ports. When the T/R input is LOW, data flows from the B ports to the A ports.

What is the function of the Output Enable input?

When the OE input is HIGH, both A and B ports are disabled and placed in a High Z state, effectively disconnecting them from the bus.