STMicroelectronics M74HC573TTR

Overview

M74HC573TTR from STMicroelectronics is a high-speed CMOS octal D-type transparent latch with 3-state non-inverting outputs, designed for bus-oriented data latching in digital systems. It features 8-bit parallel data storage, latch enable (LE) and output enable (OE) control, 2V–6V supply operation, 13ns typical propagation delay at 6V, and ±6mA output drive capability.

For engineers reviewing the M74HC573TTR datasheet, M74HC573TTR pinout, M74HC573TTR application, or M74HC573TTR equivalent, this device is selected for bidirectional bus isolation, address/data latching in microcontroller peripherals, and level-shifted I/O buffering where low-power, noise-immune, and pin-compatible 74-series logic is required.

Technical Context

The M74HC573TTR implements a transparent latch architecture: when LE is HIGH, Q outputs mirror D inputs in real time; when LE transitions LOW, the Q outputs freeze the instantaneous D input state. Its 3-state outputs are controlled independently by OE (active-LOW), enabling shared-bus arbitration without external gating.

Designed using silicon gate C2MOS technology, it delivers symmetrical output impedance (|IOH| = IOL ≥ 6mA), balanced tPLH/tPHL delays, and high noise immunity (VNIH/VNIL ≥ 28% VCC), supporting reliable operation across industrial temperature ranges (−55°C to +125°C) and supply voltages from 2V to 6V.

Key Specifications

Pinout & Package

TSSOP-20 package (6.5mm × 4.4mm, 0.65mm pitch), lead-free and RoHS-compliant, optimized for high-density PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal transparent latch applications.

Compared with SN74HC573PWR and 74VHC573FT, the M74HC573TTR offers superior high-temperature reliability (125°C operation), tighter noise immunity spec (28% VCC), and broader industrial qualification - making it optimal for harsh-environment control systems where thermal margin and EMC robustness are critical.

Availability

M74HC573TTR is available at Aetrix Electronics and suitable for microcontroller bus interfacing, industrial PLC expansion, automotive body control units, and automated test equipment requiring stable component supply and long-lifecycle support.

Supply support for M74HC573TTR 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 and broad analog/mixed-signal portfolio.

The M74HC573TTR belongs to ST's high-speed HC logic family, engineered for seamless migration from legacy TTL systems while delivering lower power, wider voltage tolerance, and enhanced noise resilience in real-world industrial deployments.

FAQ

What is the maximum clock frequency supported by the M74HC573TTR?

The M74HC573TTR is not a clocked register but a transparent latch with no internal clock. Its effective maximum data rate depends on propagation delay and setup/hold timing: with tPD = 13ns (typ.) and ts = 3ns (min.), it supports reliable latching of signals up to ~30 MHz when driven by clean, edge-controlled LE pulses meeting minimum pulse width (7ns min. at 6V).

Can M74HC573TTR operate at 3.3V with guaranteed performance?

Yes - the device is fully specified from 2V to 6V. At VCC = 3.3V, DC parameters include VIH = 2.31V (min.), VOL = 0.26V (max. at 6mA), and tPD = 18ns (max. over temperature), ensuring compatibility with 3.3V LVTTL and LVCMOS interfaces without level translation.

Is there a pin-compatible 16-bit version of this latch?

No - ST does not offer a single-package 16-bit HC latch. System designers achieve 16-bit latching using two M74HC573TTR devices with shared LE and OE signals. This approach preserves timing alignment and simplifies layout versus monolithic alternatives with different pinouts or timing skews.

Does M74HC573TTR require external pull-up or pull-down resistors on OE or LE?

Not inherently - OE and LE are CMOS inputs with ≤1µA leakage. However, in floating or high-noise environments, a 10kΩ pull-down on OE ensures default high-impedance output state at power-up, and a pull-up on LE prevents unintended latching during reset; these are design best practices, not datasheet requirements.