STMicroelectronics 74LVQ574TTR

Overview

74LVQ574TTR from STMicroelectronics is a low-voltage CMOS octal D-type flip-flop with non-inverting 3-state outputs, designed for 3.3V bus interface and data latching in high-speed digital systems. It features 180 MHz max clock frequency (typ.), 2V–3.6V operating voltage, and symmetrical 12 mA output drive at 3.0V, enabling robust PCI-bus-level signaling at 24 mA.

For engineers reviewing the 74LVQ574TTR datasheet, 74LVQ574TTR pinout, 74LVQ574TTR application, or 74LVQ574TTR equivalent, key selection criteria include propagation delay matching (tPLH ≅ tPHL), 3-state enable timing (tPLZ/tPZL ≤ 12 ns), 75Ω transmission line driving capability, and ESD immunity (2 kV HBM).

Technical Context

The device operates on positive-edge clock triggering with independent 3-state control via active-low OE, allowing latch retention and data update while outputs are tri-stated. Its sub-micron C2MOS process ensures low noise (VOLP = 0.5 V typ.) and low quiescent current (ICC = 4 µA max at 25°C).

All inputs/outputs feature integrated protection circuits, supporting −55°C to +125°C operation and 2 kV ESD immunity. Pin layout separates inputs (D0–D7, CK, OE) and outputs (Q0–Q7) across opposite package sides to simplify PCB routing and reduce crosstalk.

Key Specifications

Pinout & Package

TSSOP-20 package (6.5 mm × 4.4 mm, 0.65 mm pitch) with gull-wing leads, optimized for high-density PCB layouts and thermal performance in industrial environments.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC574APWR and 74ALVC574PW, the 74LVQ574TTR uniquely balances 180 MHz performance, 2 kV ESD robustness, and 2.0 V minimum supply-making it optimal for industrial backplanes and automotive modules where reliability and voltage margin are prioritized over marginal speed gains.

Availability

74LVQ574TTR is available at Aetrix Electronics and suitable for industrial PLC backplane interfaces, automotive body control modules, and medical imaging signal conditioning boards requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74LVQ574TTR 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 microcontrollers, power management, analog, and automotive-grade ICs with vertical manufacturing capabilities.

The 74LVQ series targets low-voltage, low-noise 3.3V digital interface applications, emphasizing robustness, timing precision, and compatibility with legacy TTL and PCI standards in industrial and automotive systems.

FAQ

What is the minimum valid clock pulse width for reliable operation?

The minimum clock pulse width (HIGH or LOW) is 3.0 ns (typ.) at VCC = 3.3V, with a maximum of 4.0 ns across the full −55°C to +125°C temperature range. This specification ensures reliable edge detection and avoids metastability in synchronous latch behavior under worst-case voltage and temperature conditions.

Can the 74LVQ574TTR operate with a 2.5V supply and still meet PCI bus drive requirements?

Yes - at VCC = 2.5V, the device delivers ≥12 mA output drive (|IOH| = |IOL|), satisfying PCI bus loading specifications. However, maximum clock frequency drops to 100 MHz (typ.), and VIH/VIL thresholds shift accordingly; design validation at 2.5V must confirm timing closure with target load capacitance and trace impedance.

How does the 3-state enable timing affect bus arbitration in multi-master systems?

tPLZ (enable-to-output-low) and tPZH (enable-to-output-high) are both ≤12.0 ns (max) at VCC = 3.3V, ensuring rapid bus release after OE assertion. This allows fast turnaround in shared-bus protocols like ISA or custom parallel interfaces, minimizing dead time between master transmissions and preventing bus contention.

Is the 74LVQ574TTR pin-compatible with standard 74HC574 in SO-20 packages?

Yes - the 74LVQ574TTR is functionally and pinout-compatible with 74-series 574 devices, including 74HC574, but uses TSSOP-20 instead of SO-20. Physical replacement requires footprint adaptation; electrical compatibility is maintained for VCC ≤ 3.6V, though HC-family devices lack 2 kV ESD rating and 75Ω line-driving validation.