NXP Semiconductors 74HC595PW/AUJ

Overview

74HC595PW/AUJ from NXP Semiconductors is an 8-bit serial-in, serial-or-parallel-out shift register with storage latches and 3-state outputs, designed for serial-to-parallel data expansion in microcontroller I/O-constrained systems. It features separate shift and storage clocks (SHCP/STCP), asynchronous master reset (MR), and output enable (OE) control. Confirmed parameters include 100 MHz typical shift-out frequency, −40 °C to +125 °C operating range, and TSSOP16 package.

For engineers reviewing the 74HC595PW/AUJ datasheet, 74HC595PW/AUJ pinout, 74HC595PW/AUJ application, or 74HC595PW/AUJ equivalent, key selection considerations include its dual-clock architecture for glitch-free output updates, 3-state bus driver capability for shared-bus interfacing, and compatibility with 2.0–6.0 V supply rails across industrial temperature grades.

Technical Context

The 74HC595PW/AUJ implements a two-stage pipeline: an 8-bit serial shift register accepting data on SHCP rising edges, and a parallel-output storage register loaded on STCP rising edges-enabling independent clocking to prevent output corruption during shifting. Its MR input asynchronously clears all shift stages, while OE controls high-impedance state of all eight Q0–Q7 outputs.

It supports cascading via Q7S serial output and delivers rail-to-rail CMOS logic levels with VOH ≥ 4.32 V (VCC = 4.5 V, IO = −6 mA) and VOL ≤ 0.33 V (VCC = 4.5 V, IO = 6 mA). Propagation delays are specified at 19 ns (SHCP→Q7S) and 20 ns (STCP→Qn) under 4.5 V/25 °C conditions.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC595PWR, the 74HC595PW/AUJ offers extended temperature support and identical NXP logic family behavior; versus 74AHC595PW, it trades peak speed for broader input voltage noise margin and proven robustness in mixed-signal industrial layouts.

Availability

74HC595PW/AUJ is available at Aetrix Electronics and suitable for LED display drivers, microcontroller I/O expansion, industrial serial bus nodes, and remote control latching requiring stable component supply across extended temperature ranges.

Supply support for 74HC595PW/AUJ 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The 74HC595PW/AUJ belongs to NXP's legacy HC logic family, engineered for low-power, high-noise-immunity digital interfacing in cost-sensitive embedded systems requiring reliable serial-to-parallel conversion.

FAQ

What is the maximum clock frequency supported by the 74HC595PW/AUJ?

The 74HC595PW/AUJ supports a typical maximum shift clock (SHCP) frequency of 100 MHz at VCC = 4.5 V and 25 °C. At the full −40 °C to +125 °C range and VCC = 4.5 V, the guaranteed minimum fmax is 24 MHz. The storage clock (STCP) has identical timing limits. These values are measured with defined load conditions (CL = 50 pF, RL = 1 kΩ) per the official NXP datasheet Rev. 7.

Does the 74HC595PW/AUJ support daisy-chaining with other shift registers?

Yes, the 74HC595PW/AUJ supports daisy-chaining via its Q7S (pin 9) serial output. This pin carries the most significant bit shifted out of the internal register, allowing direct connection to the DS (pin 14) input of a second 74HC595PW/AUJ. Cascading preserves the same clock and control signals across all devices, enabling scalable 16-, 24-, or N×8-bit output expansion without additional MCU pins.

How does the master reset (MR) pin affect the output latches in the 74HC595PW/AUJ?

The MR pin in the 74HC595PW/AUJ asynchronously resets only the 8-bit shift register stages-not the storage register or output latches. When MR is pulled LOW, all shift register bits clear to 0, but Q0–Q7 retain their previously latched values until the next STCP pulse. This behavior allows safe initialization of incoming data flow without disrupting currently displayed or driven outputs.

What is the purpose of the output enable (OE) pin on the 74HC595PW/AUJ?

The OE (output enable) pin on the 74HC595PW/AUJ is an active-LOW control that places all eight Q0–Q7 parallel outputs into high-impedance (Hi-Z) state when asserted. This feature enables safe sharing of output lines with other devices on a common bus, supports flicker-free blanking in LED displays, and permits hot-swapping or dynamic reconfiguration without short-circuit risk. OE operates independently of STCP and MR.

Is the 74HC595PW/AUJ compatible with 3.3 V microcontrollers?

Yes, the 74HC595PW/AUJ is fully compatible with 3.3 V microcontrollers. Its input thresholds (VIH = 2.1 V min at VCC = 3.3 V) accept standard 3.3 V logic HIGH, and its outputs swing rail-to-rail (VOH ≈ VCC, VOL ≈ 0 V), delivering valid 3.3 V logic levels. With VCC supplied at 3.3 V, it draws < 80 µA quiescent current and maintains full functionality across −40 °C to +125 °C.