onsemi MC74LVX574DT

Overview

MC74LVX574DT from onsemi is an octal D-type flip-flop with 3-state outputs, designed for high-speed data latching and bus isolation in mixed-voltage systems. It operates from 2.0 V to 3.6 V, tolerates 5.5 V inputs, delivers 8.5 ns typical propagation delay at 3.3 V, and supports −40 °C to +85 °C industrial temperature range - used in address/data bus buffering for FPGA-to-ASIC interfaces.

For engineers reviewing the MC74LVX574DT datasheet, pinout, applications, or equivalent options, key selection criteria include 3-state output timing (tPZL/tPLZ ≤ 16.3 ns), input voltage tolerance (up to 5.5 V), low ICC (4 µA max), noise immunity (VOLP ≤ 0.8 V), and TSSOP-20 package compatibility with space-constrained PCB layouts.

Technical Context

The MC74LVX574DT implements eight edge-triggered D-type latches synchronized to a single clock (CP) input, with global 3-state control via OE. All outputs enter high-impedance state when OE is high, enabling bidirectional bus sharing without external logic.

Its CMOS design ensures balanced tPLH/tPHL propagation delays (≤15.5 ns at 3.3 V, CL = 15 pF), low output skew (≤1.5 ns), and robust latch-up immunity (>100 mA). Input clamping and power-down protection allow safe interfacing between 3.3 V logic and legacy 5 V subsystems.

Key Specifications

Pinout & Package

TSSOP-20 package (Case 948E), 0.65 mm pitch, 6.5 mm × 4.4 mm body, 1.2 mm max height - optimized for automated SMT assembly and thermal dissipation in dense logic clusters.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC574APWR and 74LVX574M, the MC74LVX574DT provides unique 5.5 V input tolerance in a compact TSSOP-20 footprint - making it optimal for space-constrained industrial designs requiring mixed-voltage interoperability without level-shifting components.

Availability

MC74LVX574DT is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, FPGA configuration latching, automotive body control modules, and test equipment digital pattern generation requiring stable component supply across multi-year production cycles.

Supply support for MC74LVX574DT 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, logic, and sensing solutions for automotive, industrial, and cloud infrastructure markets.

The MC74LVX574DT belongs to the LVX low-voltage CMOS logic family, engineered for high-speed, low-power, mixed-voltage interfacing in industrial control and programmable logic systems.

FAQ

What is the maximum clock frequency supported by the MC74LVX574DT?

The MC74LVX574DT supports a maximum clock frequency of 80 MHz at VCC = 3.3 V with CL = 15 pF, and 75 MHz across the full −40 °C to +85 °C temperature range. This is derived from the AC Electrical Characteristics table specifying fmax = 80 MHz (min) under those conditions. The MC74LVX574DT achieves this performance while maintaining tight output skew (<1.5 ns) and low propagation delay (8.5 ns typ).

Does the MC74LVX574DT require external pull-up or pull-down resistors on unused inputs?

Yes - per the Recommended Operating Conditions note, all unused inputs of the MC74LVX574DT must be tied to a valid logic level (VCC or GND) to prevent floating nodes that could cause excessive current draw or metastability. The MC74LVX574DT does not integrate internal weak pull-ups/pull-downs, so external termination is mandatory for reliability in production systems.

Can the MC74LVX574DT drive a 50 pF load reliably at 3.3 V?

Yes - the MC74LVX574DT is characterized for CL = 50 pF in its AC Electrical Characteristics table, with tPLH/tPHL ≤ 19.0 ns and tPZL/tPLZ ≤ 22.0 ns at VCC = 3.3 V. Its ±4 mA output drive strength ensures stable signal edges into 50 pF loads, including PCB trace capacitance and scope probe loading, without waveform degradation.

Is the MC74LVX574DT pin-compatible with standard 74-series octal latches like the 74HC574?

No - while functionally similar, the MC74LVX574DT uses a different pinout than the 74HC574. In the MC74LVX574DT (TSSOP-20), D0–D7 occupy pins 1–8 and O0–O7 occupy pins 9–16, whereas the 74HC574 places outputs on pins 1–8 and inputs on pins 11–18. Direct replacement would require PCB redesign; the MC74LVX574DT is pin-compatible only with other LVX574 variants (e.g., MC74LVX574DTR2G).

What is the thermal resistance (θJA) of the MC74LVX574DT in its TSSOP-20 package?

The MC74LVX574DT in TSSOP-20 package has a junction-to-ambient thermal resistance (θJA) of 150 °C/W, as specified in the Maximum Ratings table. This value assumes measurement on an FR4 board with minimum pad spacing (JESD51-7), and implies a maximum power dissipation of ~833 mW at 25 °C ambient - consistent with its rated PD of 833 mW in still air.