Texas Instruments

CD74HCT688E

CD74HCT688E Description

The CD74HCT688E from Texas Instruments is an 8-bit identity comparator belonging to the 74HCT series, designed for high-speed digital logic applications. Housed in a 20-pin DIP package, this through-hole-mount IC operates within a 4.5V to 5.5V supply range, making it compatible with standard TTL and CMOS logic levels. It features an active-low output that asserts low when the two 8-bit input words (A and B) are identical, implementing the A=B function. With a maximum propagation delay of 34ns at 4.5V and 50pF load, it ensures rapid signal processing, while its low quiescent current (8 µA) minimizes power consumption. The device is RoHS3 compliant and adheres to REACH and EAR99 regulations, ensuring environmental and export compliance.

CD74HCT688E Features

• High-Speed Operation: 34ns propagation delay at 4.5V enables efficient real-time comparison.
• Low Power Consumption: 8 µA quiescent current ideal for battery-sensitive designs.
• Wide Voltage Compatibility: 4.5V–5.5V supply range ensures interoperability with 5V TTL/CMOS systems.
• Active-Low Output: Simplifies logic-level interfacing with downstream circuits.
• Robust Design: 4mA output drive capability (sink/source) ensures reliable signal integrity.
• Environmental Compliance: RoHS3, REACH Unaffected, and EAR99 certified for global use.
• Through-Hole Package: 20-pin DIP facilitates easy prototyping and breadboarding.

CD74HCT688E Applications

The CD74HCT688E excels in systems requiring bit-pattern matching or equality detection, such as:

• Microcontroller/Memory Address Decoding: Validates address or data bus integrity.
• Digital Control Systems: Compares sensor inputs or command signals for fault detection.
• Test Equipment: Verifies expected vs. actual data in automated test sequences.
• Communication Interfaces: Ensures correct packet or header alignment in serial protocols.
  Its low propagation delay and TTL-compatible inputs make it ideal for high-speed digital designs, while its low power suits portable electronics.

Conclusion of CD74HCT688E

The CD74HCT688E stands out as a high-performance, low-power identity comparator for 5V logic systems. Its fast response time, CMOS/TTL compatibility, and ease of integration make it a preferred choice for address decoding, data validation, and control logic. With Texas Instruments' reliability and compliance with global standards, this IC is a robust solution for both industrial and consumer electronics demanding precision and efficiency.