MC74ACT245DTR2

Overview

The MC74ACT245DTR2 is an octal bidirectional transceiver from the 74ACT series, manufactured by onsemi. It features eight non-inverting buffers with three-state outputs and TTL-compatible inputs. The device operates within a supply voltage range of 4.5 V to 5.5 V. It provides a current sinking capability of 24 mA at both A and B ports. The propagation delay is typically 4.0 ns at 5.0 V with a 50 pF load. The component is housed in a TSSOP-20 package.

Feature Summary

• TTL compatible inputs for direct interface with TTL logic systems
• Bidirectional data path controlled by Transmit/Receive input
• Three-state outputs allowing connection to bus lines

Applications

• Bus-oriented applications requiring data direction control
• Memory address driving
• TTL level bus oriented transceiver applications

Procurement Notes

Verify that the specific ordering suffix matches the required tape and reel packaging specifications. Confirm the device marking corresponds to the ACT logic family variant rather than the standard AC version. Ensure the package type aligns with the design footprint requirements before finalizing procurement orders.

Selection Notes

Select this component when TTL-compatible inputs are necessary alongside high-speed CMOS performance. The 24 mA output drive capability supports heavy bus loading conditions. Verify that the operating temperature range meets the environmental constraints of the target application board.

Part Context

This part belongs to the MC74AC245/74ACT245 family of octal bidirectional transceivers. The ACT variant specifically adds TTL compatibility to the inputs while maintaining the high-speed characteristics of the AC series. It serves as a bridge between different logic families in mixed-voltage digital systems.

Replacement Considerations

MC74ACT245DWR2G (SOIC-20 Tape & Reel)

FAQ

What determines the direction of data flow?

The Transmit/Receive (T/R) input determines the direction. Transmit (active-HIGH) enables data from A to B, while Receive (active-LOW) enables data from B to A.

How does the Output Enable input function?

When the Output Enable (OE) input is HIGH, it disables both A and B ports by placing them in a High Z condition.