STMicroelectronics M74HC164B1R

Overview

M74HC164B1R from STMicroelectronics is a high-speed CMOS 8-bit serial-in, parallel-out (SIPO) shift register with dual data inputs (A/B), asynchronous master clear, and edge-triggered clock. It operates from 2V to 6V, delivers tPLH/tPHL ≈ 27 ns (typ. at VCC = 6V), supports 62 MHz max clock frequency, and drives ±4 mA outputs. It is used in LED matrix drivers, address latching, and I/O expansion where compact serial-to-parallel conversion is required.

For engineers reviewing the M74HC164B1R datasheet, M74HC164B1R pinout, M74HC164B1R application, or M74HC164B1R equivalent, key selection criteria include asynchronous reset behavior, dual-input NAND logic for data enable, symmetrical output drive strength, propagation delay matching, and DIP-14 package compatibility with legacy 74-series layouts.

Technical Context

The M74HC164B1R implements an 8-stage shift register using silicon gate C2MOS technology, with data entered serially via A or B (either acting as active-high enable for the other). Each rising clock edge loads QA with the NAND of A and B, shifting prior stage values rightward.

It features true asynchronous clear (active-low, overriding all inputs), input protection against ESD and transient overvoltage, and rail-to-rail output swing with balanced |IOH| = |IOL| ≥ 4 mA under load. Propagation delays tPLH and tPHL are matched within 10% across temperature and voltage.

Key Specifications

Pinout & Package

Package: Plastic Dual In-line Package (DIP-14), 14-pin through-hole, 2.54 mm pitch, JEDEC MS-001 compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC164N and 74AHC164PW, the M74HC164B1R offers superior low-power performance in through-hole form factor, making it optimal for cost-sensitive industrial controls where thermal margin and legacy assembly processes matter.

Availability

M74HC164B1R is available at Aetrix Electronics and suitable for LED display drivers, microcontroller I/O expanders, and industrial address latching requiring stable component supply across extended temperature ranges (-55°C to +125°C).

Supply support for M74HC164B1R 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 vertical manufacturing capabilities.

The M74HC164B1R belongs to ST's high-speed CMOS logic family, designed specifically for robust, low-power serial-to-parallel conversion in harsh-environment industrial and appliance control systems.

FAQ

What is the function of the dual data inputs A and B?

Inputs A and B feed an internal NAND gate whose output enters QA on each rising clock edge. Either input can act as an active-high enable for the other: if A is held high, data on B passes through; if B is high, data on A passes. An unused input must be tied high or both inputs connected together to avoid floating states.

Does the CLEAR input require a debounced signal?

No - the CLEAR input is fully asynchronous and internally synchronized to avoid metastability. It overrides all other inputs immediately upon going low, forcing all Q outputs low within tPHL(CLR→Q) ≤ 45 ns (max. at VCC = 6 V, -55°C to +125°C), even during active clocking.

Can M74HC164B1R operate reliably at 3.3 V?

Yes - it is fully specified from 2.0 V to 6.0 V. At VCC = 3.3 V, VOH ≥ 3.15 V and VOL ≤ 0.33 V (with 4 mA load), meeting 3.3 V LVTTL logic thresholds. Propagation delay increases to ~40 ns (typ.), remaining suitable for most microcontroller-driven applications.

Is there a surface-mount version of this part?

Yes - ST offers SOP-14 (M74HC164M1R) and TSSOP-14 (M74HC164TTR) variants. The M74HC164B1R is DIP-14 only. Pinout and logic function are identical across packages, but AC characteristics differ slightly due to parasitic capacitance variations.