Texas Instruments SN74HC595NSR-P

Overview

SN74HC595NSR-P from Texas Instruments is an 8-bit serial-in, parallel-out shift register with 3-state output registers, used for bus expansion and LED multiplexing in microcontroller-based systems. It operates from 2 V to 6 V, delivers ±6 mA output drive at 5 V, features separate SRCLK and RCLK clocks, and includes direct clear (SRCLR) and output enable (OE) control - enabling cascaded LED display drivers and I/O port extenders.

For engineers reviewing the SN74HC595NSR-P datasheet, SN74HC595NSR-P pinout, SN74HC595NSR-P application, or SN74HC595NSR-P equivalent, key selection criteria include its 3-state parallel outputs, 13 ns typical propagation delay, 80 µA max ICC, wide 2–6 V supply range, and SOP-16 package compatibility with high-density PCB layouts.

Technical Context

The SN74HC595NSR-P integrates two synchronous stages: a serial-input shift register clocked by SRCLK and an 8-bit D-type storage register clocked by RCLK - both positive-edge triggered. This dual-clock architecture enables independent data shifting and latching, eliminating output glitches during update cycles.

Its 3-state outputs (QA–QH) are controlled by OE, allowing bus sharing without contention; SRCLR asynchronously clears the shift register; QH′ provides serial cascade output. All inputs tolerate voltages up to 5.5 V regardless of VCC, supporting mixed-voltage interface design.

Key Specifications

Pinout & Package

SOP-16 (Small Outline Package), 16-pin surface-mount, body size 9.90 mm × 3.90 mm, RoHS-compliant, tape-and-reel packaging (2000 pcs/reel).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar shift register applications.

Compared with SN74HC165N and 74LV595PW, the SN74HC595NSR-P uniquely combines serial-in/parallel-out functionality, 3-state outputs, and dual-clock latching - making it the only option among the three capable of glitch-free, cascaded LED display control at 2–6 V.

Availability

SN74HC595NSR-P is available at Aetrix Electronics and suitable for LED signage, industrial PLC I/O expansion, and network equipment indicator logic requiring stable component supply across automotive-qualified temperature ranges and long production lifecycles.

Supply support for SN74HC595NSR-P 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions with decades of industry-standard product development.

The SN74HC595NSR-P belongs to TI's HC logic family, designed specifically for low-power, high-noise-immunity CMOS applications where reliable serial-to-parallel conversion and bus isolation are required.

FAQ

What is the maximum clock frequency supported by the SN74HC595NSR-P?

The SN74HC595NSR-P supports up to 25 MHz maximum clock frequency at VCC = 5 V and TA = 25 °C, as specified in the timing requirements table. At 2 V operation, the maximum SRCLK frequency drops to 5 MHz. These limits ensure setup/hold time compliance and stable data capture across temperature and voltage corners.

Can the SN74HC595NSR-P drive LEDs directly without current-limiting resistors?

No, the SN74HC595NSR-P must always be used with external current-limiting resistors on QA–QH outputs. While it provides ±6 mA drive capability at 5 V, exceeding 35 mA per output or 70 mA total device current risks permanent damage. Resistors ensure safe LED forward current and prevent thermal overstress.

How does the SN74HC595NSR-P handle cascading multiple devices?

The SN74HC595NSR-P supports seamless cascading via its QH′ (pin 9) serial output, which connects directly to the SER input of the next device. With synchronized SRCLK and RCLK across all stages, a single 24-bit serial stream can update three devices simultaneously - maintaining alignment between shift and latch operations.

Is the SN74HC595NSR-P pin-compatible with other 74HC595 variants in SOP-16 packages?

Yes, the SN74HC595NSR-P shares identical pinout, electrical characteristics, and functional behavior with all other SN74HC595 variants in SOP-16 (NS) packaging, including SN74HC595NSR and SN74HC595NSRG4. Differences are limited to packaging markings, reel specifications, and RoHS compliance documentation - not pin function or timing.

What is the purpose of the SRCLR pin on the SN74HC595NSR-P?

The SRCLR (pin 10) is an asynchronous active-low input that forces all bits in the shift register to logic 0, independent of SRCLK or RCLK. This provides deterministic initialization or emergency reset - especially useful during power-up sequencing or fault recovery to prevent undefined output states before valid data is loaded.