STMicroelectronics M74HCT164RM13TR

Overview

M74HCT164RM13TR from STMicroelectronics is a high-speed CMOS 8-bit serial-in, parallel-out (SIPO) shift register with TTL-compatible inputs, 24 ns typical propagation delay at 4.5 V, ±4 mA symmetrical output drive, and asynchronous master clear. It operates from 4.5–5.5 V, supports -55°C to +125°C industrial temperature range, and is used in LED display drivers and microcontroller GPIO expansion.

For engineers reviewing the M74HCT164RM13TR datasheet, M74HCT164RM13TR pinout, M74HCT164RM13TR application, or M74HCT164RM13TR equivalent, key selection criteria include SIPO timing integrity, dual-input data enable logic, asynchronous reset behavior, and TSSOP-14 package compatibility with high-density PCB layouts.

Technical Context

The device implements an 8-stage shift register with edge-triggered clock (LOW-to-HIGH), NAND-combined serial inputs (A and B), and asynchronous active-low CLEAR that forces all Q outputs low regardless of clock or data state. Data entry requires one input held high while the other serves as enabled serial path.

It uses silicon gate C2MOS technology for TTL-level input compatibility (VIH ≥ 2.0 V, VIL ≤ 0.8 V), features balanced tPLH/tPHL propagation delays, and includes built-in ESD protection on all inputs. Output impedance symmetry ensures consistent rise/fall times under load.

Key Specifications

Pinout & Package

TSSOP-14 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 8-bit SIPO shift register applications.

Compared with SN74HCT164DR and 74LV164PW, the M74HCT164RM13TR delivers superior thermal dissipation in TSSOP-14, guaranteed 5 V TTL interoperability without translation, and lowest quiescent current across full temperature range - making it optimal for space-constrained, high-reliability 5 V industrial interfaces.

Availability

M74HCT164RM13TR is available at Aetrix Electronics and suitable for LED display drivers, microcontroller GPIO expansion, and industrial control logic requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for M74HCT164RM13TR 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, specializing in automotive, industrial, and power management ICs with broad analog, digital, and mixed-signal portfolios.

The M74HCT164 belongs to ST's HCT logic family, designed specifically for seamless integration between legacy TTL systems and modern CMOS microcontrollers in harsh-environment industrial controls and instrumentation.

FAQ

Can M74HCT164RM13TR operate at 3.3 V?

No. The device is specified only for 4.5–5.5 V operation. At 3.3 V, input thresholds (VIH ≥ 2.0 V) become marginal, output drive collapses below specification, and AC timing parameters are not guaranteed. Use 74LV164 or 74LVC164 for true 3.3 V compatibility.

What happens if both A and B inputs are low?

When both A and B are low, the internal NAND gate produces a high level at the serial input node. On the next rising clock edge, QA will go high - effectively injecting a logic '1' into the register regardless of prior state. This behavior is defined in the truth table and must be accounted for in control software.

Is the CLEAR input debounced internally?

No. CLEAR is a purely asynchronous, unbuffered input with no internal filtering or hysteresis. External RC filtering or firmware debouncing is required in noisy environments to prevent spurious resets caused by glitches or contact bounce on the CLEAR line.

Does M74HCT164RM13TR support hot insertion?

No. The device lacks hot-swap protection circuitry. Applying VCC before GND, or connecting signals before power stabilization, may cause latch-up or permanent damage due to internal parasitic SCR activation. Always follow proper power sequencing: GND first, then VCC, then signals.