STMicroelectronics 74AC573MTR

Overview

74AC573MTR from STMicroelectronics is a high-speed CMOS octal D-type latch with non-inverting 3-state outputs. The device contains eight transparent latches controlled by a common latch-enable input and a common active-low output-enable input, making it suitable for bus latching, temporary data storage, microcontroller expansion, address holding, and synchronous digital interface buffering.

For engineers reviewing the 74AC573MTR datasheet, 74AC573MTR pinout, 74AC573MTR application, or 74AC573MTR equivalent, this logic IC is most relevant for 8-bit bus interface circuits, memory address latches, MCU data buffers, peripheral control staging, and CMOS logic systems requiring 2 V to 6 V operation, high-speed AC-family timing, 3-state bus isolation, strong CMOS output drive, and SO-20 tape-and-reel assembly.

Technical Context

74AC573MTR uses eight level-sensitive D latches. When LE is high, each Q output follows the corresponding D input if the output stage is enabled; when LE is low, the logic level present at D0 to D7 is stored internally. The active-low OE input controls only the 3-state output buffers, so the latch can retain or update data while the external bus remains isolated.

The device belongs to ST's 74AC high-speed CMOS logic family and operates from a 2 V to 6 V supply range. AC-family output drive supports balanced CMOS bus operation, while the low static current and high noise immunity make the part useful in digital boards that need a fast 8-bit transparent latch rather than an edge-triggered register.

Key Specifications

Pinout & Package

74AC573MTR is supplied in an SO-20 package for surface-mount assembly. The 20-pin small-outline package provides a conventional octal-latch layout with active-low OE at pin 1, latch enable at pin 11, VCC and GND supply pins at opposite sides, and paired data/output signal placement for efficient routing in 8-bit bus, memory-address, and control-signal latch layouts.

Key Features

• Octal D-type transparent latch with eight non-inverting 3-state outputs.
• Common latch-enable input controls transparent data flow and internal data storage.
• Common active-low output-enable input provides high-impedance bus isolation.
• 2 V to 6 V operating supply range for CMOS logic systems.
• High-speed AC-family CMOS timing with low static power consumption.
• Symmetrical high-current CMOS output drive for bus and control-line buffering.
• Inputs and outputs include static-discharge protection structures.
• SO-20 package supplied in tape-and-reel format for automated surface-mount production.

Applications

Equivalent & Alternatives

When evaluating 74AC573MTR equivalent devices, engineers should compare logic family, package footprint, supply range, input threshold family, latch-enable behavior, OE polarity, output-drive capability, propagation delay, output loading, and whether the PCB requires SO-20 or TSSOP-20 assembly.

Compared with 74AC573TTR, 74AC573MTR keeps the same octal transparent latch function, LE / OE control behavior, output polarity, and AC-family CMOS operation, with the main difference being the SO-20 package format. 74AC573MTR vs 74ACT573MTR selection depends on CMOS versus TTL input-threshold requirements as well as replacement footprint compatibility.

Quality

74AC573MTR should be sourced as original STMicroelectronics components through traceable and controlled supply channels. Quality verification procedures may include SO-20 package inspection, top-mark validation, tape-and-reel label review, solderability testing, lead coplanarity inspection, VCC / GND continuity checks, LE transparent-mode testing, latch-hold verification, OE high-impedance testing, output-level testing, and incoming inspection according to digital logic production requirements.

Availability

74AC573MTR is available at Aetrix Electronics and suitable for bus latches, memory-address holding, microcontroller expansion circuits, peripheral control staging, digital interface buffers, and 8-bit CMOS logic systems requiring stable component supply and repeatable production support.

Supply support may include scheduled delivery planning, volume procurement support, BOM continuity assistance, traceable sourcing management, and long-term availability support for industrial controller manufacturers, consumer electronics builders, repair groups, contract manufacturers, embedded hardware developers, and legacy logic-board owners.

For production deployment, confirming the SO-20 footprint, tape-and-reel format, 2 V to 6 V logic supply, CMOS input-threshold requirement, LE timing, OE control logic, output loading, operating temperature requirement, and sourcing continuity helps reduce procurement risk and improve manufacturing stability.

Manufacturer

STMicroelectronics supplies standard logic ICs, microcontrollers, power-management ICs, sensors, analog devices, RF products, protection components, and discrete semiconductors for industrial, consumer, automotive, communication, and embedded applications. 74AC573MTR belongs to ST's AC high-speed CMOS logic portfolio for transparent latching, bus interface, buffering, and synchronous digital control functions.

FAQ

What is 74AC573MTR used for?

74AC573MTR is used as an 8-bit transparent latch and 3-state bus buffer in digital systems. It is commonly used for bus latching, memory address holding, microcontroller expansion, peripheral control staging, and temporary data storage where eight logic states must be held after a latch-enable event.

How does the LE pin work on 74AC573MTR?

74AC573MTR uses LE as the latch-enable input. When LE is high, Q0 to Q7 follow D0 to D7 if the outputs are enabled. When LE is low, the last input state is stored internally. This transparent-latch behavior differs from an edge-triggered flip-flop such as a 74AC374.

How does the OE pin work on 74AC573MTR?

74AC573MTR uses an active-low OE input. When OE is low, the stored or transparent latch states appear on Q0 to Q7. When OE is high, all eight outputs enter the high-impedance state, allowing the device to share a bus with other logic outputs without changing the internal latch state.

What supply voltage does 74AC573MTR use?

74AC573MTR operates from a 2 V to 6 V VCC supply range. The selected VCC defines the CMOS output logic levels and affects timing, drive strength, and input switching margins. The part is intended for AC-family CMOS logic systems rather than TTL-threshold ACT-family designs.

What package is used by 74AC573MTR?

74AC573MTR uses an SO-20 surface-mount package supplied in tape-and-reel format. The package provides 20 pins for OE, eight Q outputs, eight D inputs, LE, VCC, and GND, using the standard octal transparent latch pin arrangement for 74AC573 logic devices.

What is the difference between 74AC573MTR and 74AC573TTR?

74AC573MTR and 74AC573TTR provide the same STMicroelectronics octal transparent latch function, non-inverting 3-state outputs, LE control, and active-low OE behavior. The difference is package format: 74AC573MTR uses SO-20, while 74AC573TTR uses TSSOP-20 for a smaller board footprint.

What is the difference between 74AC573MTR and 74ACT573MTR?

74AC573MTR and 74ACT573MTR are related octal transparent latches, but their input threshold families differ. 74AC573MTR uses AC-family CMOS input thresholds, while 74ACT573MTR uses ACT-family TTL-compatible input thresholds. The correct choice depends on the logic levels generated by the upstream device and the required PCB footprint.