Nexperia USA Inc. 74HCT597PWJ

Overview

74HCT597PWJ from Nexperia is an 8-bit parallel-in, serial-out shift register with input flip-flops and dual edge-triggered clocks (STCP for storage, SHCP for shifting). It features TTL-compatible inputs (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 5 V), asynchronous master reset (MR), parallel load (PL), and serial data output (Q). Used in microcontroller I/O expansion, LED matrix drivers, and industrial control logic where reliable level-shifted serial data conversion is required.

For engineers reviewing the 74HCT597PWJ datasheet, 74HCT597PWJ pinout, 74HCT597PWJ application, or 74HCT597PWJ equivalent, this page delivers verified functional architecture, timing-critical parameters (tpd ≤ 60 ns @ 5 V), package-validated pin roles, and real-world use context - all extracted from Nexperia's Rev. 7 (May 2024) product data sheet.

Technical Context

The device implements two synchronized but functionally independent registers: an 8-bit parallel input storage register (clocked by STCP) feeding a serial shift register (clocked by SHCP). Both clocks are positive-edge-triggered, enabling precise phase-aligned capture and shift operations. The MR input asynchronously clears the shift register, while PL enables direct parallel-to-serial loading without intermediate clocking.

Input clamping diodes allow safe interfacing to voltages exceeding VCC when used with current-limiting resistors. TTL-level input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V at VCC = 4.5–5.5 V) ensure compatibility with legacy 5 V logic families, distinguishing it from the CMOS-input 74HC597 variant.

Key Specifications

Pinout & Package

TSSOP16 package (SOT403-1): plastic thin shrink small outline, 16 leads, 4.4 mm body width, 0.65 mm pitch - optimized for high-density PCB layouts and reflow compatibility.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74HC597PW, the 74HCT597PWJ offers guaranteed TTL input compatibility at 5 V, enabling direct connection to legacy controllers; compared with SN74LS165N, it adds dual-clock pipelining and push-pull output drive - critical for high-reliability, multi-stage serial data chains.

Availability

74HCT597PWJ is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, LED matrix row drivers, automated test equipment pattern generation, and legacy bus interface adapters requiring stable component supply across extended temperature ranges.

Supply support for 74HCT597PWJ 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, analog, and discrete components for industrial, automotive, and consumer applications.

The 74HCT597 belongs to Nexperia's 74HCT logic family - engineered specifically for seamless interoperability between TTL and CMOS systems operating at 5 V, with emphasis on noise immunity, wide temperature operation, and long-term supply stability.

FAQ

Can 74HCT597PWJ operate at 3.3 V supply?

No. The 74HCT597PWJ is specified only for VCC = 4.5 V to 5.5 V per Table 5. At 3.3 V, input thresholds (VIH ≥ 2.0 V) may not be reliably met by standard 3.3 V logic outputs, and propagation delays exceed specification. Use 74HC597PW for 3.3 V–6.0 V operation.

What is the minimum pulse width required on SHCP and STCP?

Per Table 7, tW(min) = 10 ns for both SHCP and STCP at VCC = 4.5 V. This corresponds to a maximum clock frequency of 100 MHz for pulse generation, though fmax for reliable data shifting is 20 MHz (tPHL/tPLH ≤ 40 ns). Ensure rise/fall times ≤ 6 ns (Table 9).

How does the PL (parallel load) input interact with the shift register?

PL is active LOW. When PL = LOW, the next rising edge of SHCP transfers the contents of the storage register (latched on prior STCP) directly into the shift register - bypassing normal serial shifting. This enables instantaneous parallel-to-serial conversion without waiting for 8 clock cycles.

Is the Q output capable of driving multiple 74HCT inputs?

Yes. VOH ≥ 3.7 V and VOL ≤ 0.4 V at IO = ±4.0 mA (Table 6) - sufficient to drive ≥10 standard 74HCT inputs (each drawing ≤ 40 μA) while maintaining noise margins. For heavier loads, add a buffer stage to preserve timing integrity.