STMicroelectronics M74HC165RM13TR

Overview

M74HC165RM13TR from STMicroelectronics is a high-speed CMOS 8-bit parallel-in/serial-out (PISO) shift register with asynchronous parallel load, operating from 2V to 6V supply, featuring 15ns typical propagation delay at 6V, ±4mA output drive, and pin/function compatibility with standard 74-series 165 devices - used in microcontroller GPIO expansion and industrial I/O interfacing.

For engineers reviewing the M74HC165RM13TR datasheet, M74HC165RM13TR pinout, M74HC165RM13TR application, or M74HC165RM13TR equivalent, key selection criteria include clock-edge-triggered serial shifting, dual-clock inhibit capability via NOR-gated inputs, guaranteed operation across –55°C to +125°C, and TSSOP-16 packaging for space-constrained PCB layouts.

Technical Context

The M74HC165RM13TR implements an 8-stage master-slave RS flip-flop chain with over-riding asynchronous parallel load control. Shift/load low enables transparent parallel data capture with setup/hold timing constraints; shift/load high enables clocked serial shifting on rising edges of either CLOCK or CLOCK INH (via internal 2-input NOR gate).

Its symmetrical output impedance (|IOH| = IOL ≥ 4mA), balanced tPLH/tPHL delays, and high noise immunity (VNIH/VNIL ≥ 28% VCC) support robust signal integrity in noisy industrial environments. All inputs include ESD protection diodes rated for ±20mA transient current.

Key Specifications

Pinout & Package

TSSOP-16 package: 4.9 × 6.4 mm body, 0.65 mm pitch, 1.2 mm height, lead-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC165DR and 74LV165PW, the M74HC165RM13TR uniquely combines TSSOP-16 miniaturization, dual-clock inhibit capability, and extended –55°C to +125°C qualification - making it optimal for thermally demanding, space-limited industrial and automotive control nodes.

Availability

M74HC165RM13TR is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, test equipment digital pattern capture, and legacy system interface adapters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for M74HC165RM13TR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The M74HC165RM13TR belongs to ST's high-reliability HC logic family, engineered for robust operation in harsh environments - targeting industrial automation, automotive electronics, and mission-critical control systems.

FAQ

What is the minimum setup time required for parallel data inputs relative to the SHIFT/LOAD signal?

The minimum setup time (ts) for parallel inputs (A–H) relative to SHIFT/LOAD is 5ns at VCC = 6V and TA = 25°C, per AC Electrical Characteristics table on page 5. This ensures metastability-free latching during asynchronous load; timing must be verified against actual board trace delays and driver slew rates in final layout.

Can CLOCK INH be used as a standalone clock enable without connecting the CLOCK pin?

No - CLOCK INH functions only as an inhibit input gated with CLOCK via an internal 2-input NOR gate. Both pins must be driven: CLOCK provides the edge trigger, while CLOCK INH high blocks propagation. Leaving CLOCK floating or unconnected violates Absolute Maximum Ratings and may cause undefined behavior or increased ICC.

Does the M74HC165RM13TR support hot insertion or live insertion into a powered system?

No - the device lacks hot-swap protection circuitry. Absolute Maximum Ratings specify VI limits of –0.5V to VCC + 0.5V. Applying inputs before VCC stabilization risks forward-biasing internal protection diodes, potentially causing latch-up or permanent damage. Power sequencing per manufacturer guidelines is mandatory.

How does the QH and QH output pairing support differential signaling or error checking?

QH and QH provide true/complement outputs from the same internal node, enabling simple XOR-based parity generation or glitch detection in serial streams. While not fully differential like LVDS, this pairing allows basic noise rejection in short-distance PCB traces - e.g., feeding both signals to a comparator or XOR gate to detect transition anomalies caused by EMI.