Nexperia USA Inc. 74AHCT594PW,118

Overview

74AHCT594PW,118 from Nexperia is an 8-bit non-inverting serial-in, parallel-out shift register with independent storage register, TTL-compatible input thresholds (VIH = 2.0 V, VIL = 0.8 V), dual positive-edge clocks (SHCP and STCP), and active-low asynchronous resets (SHR, STR). It operates from 4.5 V to 5.5 V across –40 °C to +125 °C and delivers 8 parallel outputs (Q0–Q7) plus cascading serial output Q7S - used in LED matrix drivers and industrial I/O expansion.

For engineers reviewing the 74AHCT594PW,118 datasheet, 74AHCT594PW,118 pinout, 74AHCT594PW,118 application, or 74AHCT594PW,118 equivalent, this device supports high-speed serial-to-parallel conversion with independent shift/storage control, Schmitt-trigger inputs for noise immunity, and overvoltage-tolerant inputs up to 5.5 V - critical for robust microcontroller peripheral interfacing.

Technical Context

The 74AHCT594PW,118 integrates two synchronous stages: a 8-stage shift register accepting serial data (DS) on SHCP rising edges, and an 8-bit D-type storage register loaded on STCP rising edges. Both registers feature dedicated active-low reset lines (SHR, STR), enabling independent clearing without affecting the other stage.

Its TTL-level input compatibility (VIH ≥ 2.0 V, VIL ≤ 0.8 V at VCC = 4.5–5.5 V) ensures direct interfacing with legacy 5 V logic families, while propagation delays as low as 3.5 ns (tPLH, VCC = 5 V, CL = 15 pF) and maximum clock frequency of 90 MHz support real-time data latching in timing-critical control systems.

Key Specifications

Pinout & Package

TSSOP16 plastic thin shrink small outline package (SOT403-1); 16 leads; body width 4.4 mm; 0.65 mm pitch; exposed pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit serial-in/parallel-out shift register with storage applications.

Compared with 74AHC594PW,118 and SN74HC595PWR, the 74AHCT594PW,118 uniquely provides TTL-compatible inputs for seamless LS-TTL replacement and dual independent resets - enabling safer, more deterministic output control in industrial and automotive systems where glitch-free initialization is mandatory.

Availability

74AHCT594PW,118 is available at Aetrix Electronics and suitable for LED display drivers, industrial I/O expanders, remote control holding registers, and automotive body controller modules requiring stable component supply across extended temperature ranges.

Supply support for 74AHCT594PW,118 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Nexperia is a global semiconductor expert delivering high-performance, reliable logic, discrete, and MOSFET solutions optimized for efficiency, miniaturization, and robustness in high-volume applications.

The 74AHCT series targets legacy TTL system upgrades and industrial control designs requiring pin-compatible, low-power replacements with guaranteed noise immunity and extended temperature operation.

FAQ

Can 74AHCT594PW,118 operate at 3.3 V?

No - the 74AHCT594PW,118 is specified only for 4.5 V to 5.5 V supply. Its TTL-compatible inputs require VIH ≥ 2.0 V, but internal logic thresholds and propagation delays are not characterized below 4.5 V. For 3.3 V operation, use the 74AHC594PW,118 variant instead.

What is the function of Q7S versus Q7?

Q7 is the parallel output of the 8-bit storage register (latched by STCP), while Q7S is the serial output of the shift register (updated on each SHCP edge). Q7S feeds the next stage's DS pin in cascaded configurations; Q7 remains stable until the next STCP pulse.

How do SHR and STR interact during simultaneous assertion?

Asserting both SHR and STR simultaneously clears both the shift register (stages 0–7) and the storage register (Q0–Q7) to logic LOW. The outputs remain LOW until new data is shifted in and latched - no race condition or undefined state occurs.

Is the exposed pad on the TSSOP16 package electrically connected?

No - the exposed pad on SOT403-1 (TSSOP16) is not electrically connected to any internal node. Nexperia specifies it may be left floating or tied to GND for mechanical stability, but it carries no electrical function and must not be soldered to a voltage plane.