Nexperia USA Inc. 74HCT573DB,112

Overview

74HCT573DB,112 from Nexperia is an octal D-type transparent latch with 3-state outputs, designed for bus-oriented digital systems requiring data latching and controlled output isolation. It features TTL-compatible input thresholds (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 5 V), operates from 4.5 V to 5.5 V, supports -40 °C to +125 °C ambient range, and delivers 18 ns typical propagation delay (Dn→Qn) at VCC = 4.5 V and CL = 50 pF - enabling reliable interfacing between microprocessors and peripheral buses.

For engineers reviewing the 74HCT573DB,112 datasheet, 74HCT573DB,112 pinout, 74HCT573DB,112 application, or 74HCT573DB,112 equivalent, key selection criteria include its active-HIGH latch enable (LE), active-LOW 3-state output enable (OE), SO20 (SOT163-1) package compatibility, guaranteed 6 mA output drive strength, and compliance with JEDEC JESD7A and JESD8C standards for industrial and extended-temperature embedded control.

Technical Context

The 74HCT573DB,112 implements eight independent D-type latches with shared LE and OE controls, operating in two distinct modes: transparent (LE = HIGH) where Qn follows Dn in real time, and latched (LE = LOW) where outputs hold the last sampled input state prior to LE's HIGH-to-LOW transition. Its TTL-level inputs ensure direct compatibility with legacy 5 V logic families without level-shifting.

Output behavior is fully decoupled from latch state: OE independently places all eight Q outputs into high-impedance (Z) mode regardless of LE or stored data, supporting bidirectional bus arbitration. Input clamp diodes allow safe interfacing with voltages exceeding VCC when used with current-limiting resistors.

Key Specifications

Pinout & Package

74HCT573DB,112 uses the SO20 (SOT163-1) plastic small outline package: 20-pin, 7.5 mm body width, 1.27 mm lead pitch, gull-wing leads, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HCT573N and 74LVC573APW, the 74HCT573DB,112 uniquely balances 5 V TTL interoperability, SO20 surface-mount reliability, and extended-temperature qualification - making it optimal for industrial control and legacy-system upgrades where voltage compatibility and thermal robustness are non-negotiable.

Availability

74HCT573DB,112 is available at Aetrix Electronics and suitable for industrial control systems, automotive engine management modules, and legacy computing hardware requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HCT573DB,112 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

Nexperia is a global semiconductor expert delivering high-performance, reliable, and efficient logic, analog, and discrete components - founded on Philips' semiconductor heritage and now serving automotive, industrial, and consumer markets.

The 74HCT573DB,112 belongs to Nexperia's industry-standard 74HCT logic family, engineered specifically for robust 5 V TTL-compatible interfacing in harsh environments where latch stability, noise immunity, and long-term supply assurance are critical.

FAQ

What is the maximum clock frequency supported by the 74HCT573DB,112 in transparent mode?

The 74HCT573DB,112 does not operate on a clock signal but functions asynchronously. In transparent mode (LE = HIGH), its maximum usable data rate is determined by propagation delay (18 ns typ) and setup/hold timing. For reliable operation, input data must be stable for ≥13 ns before and ≥5 ns after LE transitions, supporting effective bus rates up to approximately 27 MHz under ideal conditions with 50 pF load.

Can the 74HCT573DB,112 be used with 3.3 V microcontrollers?

No - the 74HCT573DB,112 requires VCC = 4.5 V to 5.5 V and has TTL-level inputs (VIH ≥ 2.0 V). Driving it directly from a 3.3 V MCU violates VIH minimum under VCC = 5 V and risks unreliable latching. Use a level translator (e.g., TXB0108) or select a 3.3 V-compatible alternative like 74LVC573APW for native interfacing.

How does the latch enable (LE) pin interact with the output enable (OE) pin?

LE and OE are fully independent controls: LE governs whether Q outputs reflect current D inputs (LE = HIGH) or hold previously latched values (LE = LOW); OE determines whether Q outputs are driven (OE = LOW) or placed in high-impedance (OE = HIGH). OE assertion does not reset or alter internal latch states - data remains preserved even when outputs are disabled.

Is the 74HCT573DB,112 qualified for automotive applications?

No - while rated for -40 °C to +125 °C, the 74HCT573DB,112 is not AEC-Q100 qualified and lacks automotive-specific reliability testing (e.g., HTOL, ESD stress beyond HBM 2 kV). It is intended for industrial and commercial applications. For automotive use, specify Nexperia's automotive-grade variants such as 74HCT573DP-Q100 (SO20, AEC-Q100 Grade 2).