NXP 74AHCT164D,118: An 8-Bit Serial-In/Parallel-Out Shift Register for High-Speed Logic Applications

In the realm of digital electronics, efficiently expanding a microcontroller's limited number of I/O pins or converting serial data streams into parallel outputs is a fundamental requirement. The NXP 74AHCT164D,118 stands as a pivotal solution, an 8-bit serial-in/parallel-out shift register engineered specifically for high-speed logic applications. This integrated circuit serves as a crucial bridge between serial data communication and parallel device control, offering a blend of performance, compatibility, and reliability.

The core functionality of the 74AHCT164D is to accept a single stream of serial data and convert it into an 8-bit parallel output. It features two serial data inputs (A1 and A2), allowing them to be wired together to form an AND gate for enabling data entry or used independently. Data is shifted through the internal eight flip-flops on the low-to-high transition of the clock (CP) input. A master reset (MR) pin, when held low, clears the entire register asynchronously, forcing all outputs (Q0 to Q7) to a low state regardless of the clock, providing immediate control.

A key advantage of this specific variant is its use of Advanced High-Speed CMOS (AHCT) technology. This architecture provides a unique blend of high-speed operation typical of CMOS while maintaining TTL-compatible input thresholds. This means it can be seamlessly interfaced with both older TTL logic families and modern microcontrollers and microprocessors operating at 3.3V or 5V, making it an exceptionally versatile component in mixed-voltage systems. The device is characterized for operation from -40°C to +125°C, ensuring robust performance across industrial applications.

The 74AHCT164D,118 is particularly valued for its high-noise immunity and low power consumption, which are inherent benefits of the CMOS technology. Its ability to drive up to 10 LSTTL loads demonstrates significant output drive capability. Typical applications include:

I/O Expansion for microcontrollers to drive LEDs, relays, or other displays.

Serial-to-Parallel Data Conversion in communication interfaces and data processing systems.

Arbitrary Waveform Generation or complex timing sequences by feeding the output back into the input.

Acting as a simple data delay element.

Housed in a space-saving SOIC-14 package, the device is ideal for modern, dense PCB designs. The suffix `,118` denotes the tape and reel packaging format, which is essential for automated assembly processes in high-volume manufacturing.

ICGOODFIND: The NXP 74AHCT164D,118 is an exemplary shift register that masterfully combines high-speed operation with broad compatibility. Its TTL-interface capability, robust output drive, and reliable performance in noisy environments make it a go-to component for designers looking to solve data conversion and I/O expansion challenges efficiently and effectively.

Keywords: Shift Register, Serial-In/Parallel-Out, AHCT Logic, TTL-Compatible, High-Speed CMOS.