74HCT245DTR2G

Overview

The onsemi 74HCT245DTR2G is an octal bus transceiver utilizing high-performance silicon-gate CMOS technology. It provides bidirectional asynchronous communication between data buses with TTL-compatible inputs and 3-state outputs. The device operates within a DC supply voltage range of 4.5 V to 5.5 V. Key electrical characteristics include a maximum propagation delay of 15 ns at 4.5 V, output drive capability supporting 15 LSTTL loads, and low input current of 1.0 µA. It features ESD protection exceeding 2000 V via the Human Body Model and latchup performance above 300 mA. The component is housed in a TSSOP-20 package.

Feature Summary

• Supports bidirectional data transmission between two 8-bit buses controlled by direction and output enable pins
• Features TTL/NMOS-compatible input levels allowing direct interfacing with CMOS, NMOS, and TTL logic
• Provides high noise immunity characteristic of CMOS devices with robust ESD protection capabilities

Applications

• Two-way asynchronous communication between data buses
• Level shifting between TTL and CMOS logic families
• Bus-oriented memory and signal switching applications

Procurement Notes

Verify the specific ordering suffix DTR2G corresponds to the TSSOP-20 tape and reel packaging configuration. Confirm that the device meets Pb-Free requirements as indicated in the datasheet. Ensure compatibility with the specified operating temperature range of -55°C to +125°C for your application environment. Cross-reference the package dimensions with your PCB footprint design to ensure proper mechanical fit.

Selection Notes

Select this component when an octal transceiver with TTL-compatible inputs is required for systems operating at 4.5 V to 5.5 V. It serves as a pin-compatible alternative to LS245 devices while offering CMOS performance benefits. Consider the 3-state output capability for bus isolation needs. Evaluate the propagation delay specifications against your system timing requirements to ensure signal integrity across the data paths.

Part Context

This part belongs to the 74HCT series of high-speed CMOS logic devices manufactured by onsemi. The 74HCT245 variant specifically functions as an octal bus transceiver. It shares the same pinout configuration as the legacy LS245 standard, facilitating drop-in replacements in existing designs. The device integrates 308 FETs or 77 equivalent gates on a single chip.

Replacement Considerations

The datasheet explicitly states the device is identical in pinout to the LS245. Designers may consider other 74HCT245 variants from different manufacturers if they maintain compatible electrical characteristics and pin assignments.