74HC243N,652

Overview

The NXP USA Inc. 74HC243N,652 is a high-speed Si-gate CMOS quad bus transceiver featuring non-inverting 3-state outputs in both send and receive directions. Designed for 4-line asynchronous 2-way data communications between data buses, it allows isolation via output enable inputs OEA and OEB. The device complies with JEDEC standard no. 7A and operates within a supply voltage range of 2.0 V to 6.0 V. It supports an ambient temperature range from -40 °C to +125 °C and includes ESD protection exceeding 2000 V (HBM) and 200 V (MM). Propagation delay is specified at 6 ns typ at 5 V with 15 pF load.

Feature Summary

• Non-inverting 3-state outputs compatible with bus systems
• Supports 2-way asynchronous data communication across four lines
• ESD protection compliant with HBM and MM standards

Applications

• Asynchronous 2-way data communications between data buses
• Bus isolation applications using independent output enable controls
• System designs requiring pin-compatible replacement for low power Schottky TTL

Procurement Notes

Verify the specific ordering suffix matches the required package type, as the 74HC243 family offers multiple options including DIP, SO, and SSOP. Confirm that the selected variant meets the necessary thermal and electrical specifications for the intended operating environment. Ensure compatibility with existing board layouts when selecting between through-hole and surface-mount packages.

Selection Notes

Select this component for applications requiring bidirectional data transfer with tri-state control. The device is suitable where low power dissipation and high speed are prioritized. Consider the available package options based on assembly requirements. Verify that the input voltage levels align with the driving logic family to ensure proper signal integrity across the full operating temperature range.

Part Context

This part belongs to the 74HC series of high-speed CMOS logic devices manufactured by NXP. The series is known for low power consumption and wide supply voltage ranges. The 74HC243 specifically functions as a bus transceiver, differing from latches or drivers by providing bidirectional flow controlled by separate enable pins for each direction.

Replacement Considerations

The datasheet notes the device is similar to the 74HC242 but features non-inverting outputs instead of inverting ones. Designers replacing other bus transceivers must verify polarity requirements. Pinout compatibility should be confirmed against legacy LSTTL designs if direct substitution is planned.