STMicroelectronics 74ACT373MTR

Overview

74ACT373MTR from STMicroelectronics is a high-speed CMOS octal D-type transparent latch with 3-state non-inverting outputs, designed for bus interface and data latching in TTL/CMOS mixed-signal systems. It features 6 ns typical propagation delay (D→Q), ±24 mA output drive, 4.5–5.5 V operating range, and pin/function compatibility with standard 74-series 373 devices. Used in address/data bus buffering and microcontroller I/O expansion.

For engineers reviewing the 74ACT373MTR datasheet, 74ACT373MTR pinout, 74ACT373MTR application, or 74ACT373MTR equivalent, key selection criteria include 3-state output control timing (tPZL/tPLZ ≤ 12.5 ns), latch enable setup/hold margins (ts = –0.5 ns, th = 0.5 ns), and 50 Ω transmission line driving capability under industrial temperature range (–55°C to +125°C).

Technical Context

The device implements a dual-control 8-bit latch architecture: LE (latch enable) controls data transparency vs. latching, while OE (output enable) independently manages 3-state output activation. Both inputs are active-low and TTL-compatible (VIH ≥ 2.0 V, VIL ≤ 0.8 V at VCC = 4.5–5.5 V).

Its sub-micron C2MOS process delivers symmetrical output impedance (|IOH| = |IOL| ≥ 24 mA), balanced propagation delays (tPLH ≅ tPHL), and 2 kV ESD immunity. All inputs/outputs include protection diodes, supporting direct interfacing between high-speed CMOS and legacy TTL/NMOS logic without external level-shifting.

Key Specifications

Pinout & Package

74ACT373MTR is supplied in a 20-pin TSSOP (Thin Shrink Small Outline Package) with 0.65 mm pitch, measuring 6.5 × 6.4 × 1.1 mm (D × E × A), optimized for high-density PCB layouts and automated SMT assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal D-type latch with 3-state output applications.

Compared with 74ACT373MTR, the 74LCX373MTR reduces supply voltage flexibility but improves power efficiency in 3.3 V domains, while SN74ACT373PW offers identical performance with alternate qualification scope-neither is drop-in compatible for 5 V-only or extended temperature (–55°C) use cases.

Availability

74ACT373MTR is available at Aetrix Electronics and suitable for microcontroller bus expansion, industrial PLC I/O modules, automotive body control units, and test equipment digital pattern generators requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74ACT373MTR 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, power, and microcontroller solutions with vertical manufacturing capabilities.

The 74ACT series targets high-speed, low-power TTL-compatible logic interfaces, specifically engineered for seamless interoperability between legacy and modern digital systems in harsh-environment applications.

FAQ

What is the maximum clock/data rate supported by 74ACT373MTR?

The 74ACT373MTR does not operate on a clock signal-it is level-sensitive and transparent while LE is HIGH. Its usable data rate depends on LE pulse width (min. 1.3 ns at 25°C) and propagation delay (6 ns typ.). With proper timing margins, it reliably supports bus handshaking up to ~80 MHz in well-designed PCB layouts with controlled impedance traces.

Can OE and LE be tied together for simplified control?

Yes, OE and LE can be connected to a single control line if simultaneous latching and output enabling is acceptable. However, this eliminates independent control of data capture vs. bus release-critical in multi-master or hot-swap systems where outputs must go high-Z before new data is latched. Separate routing is recommended for full functionality.

Is 74ACT373MTR suitable for 3.3 V logic interfacing?

No-74ACT373MTR requires 4.5–5.5 V VCC and is not 3.3 V tolerant. Its VIH minimum is 2.0 V, but input thresholds are specified only for 5 V operation. For 3.3 V systems, use 74LCX373 or 74LVC373 variants, which guarantee correct switching and drive strength at lower voltages.

Does 74ACT373MTR require external pull-up or pull-down resistors on OE or LE?

No-OE and LE have TTL-compatible input thresholds and internal noise immunity. In static control applications, they may be driven directly from MCU GPIO or logic gates. Pull-downs are only needed if floating states must be avoided during power-up or reset; a 10 kΩ resistor to GND on OE ensures default high-Z output at power-on.