Diodes Incorporated 74LVC574AQ20-13

Overview

74LVC574AQ20-13 from Diodes Incorporated is an octal D-type flip-flop with 3-state outputs in a 20-pin V-QFN4525 package, operating from 1.65V to 3.6V supply. It features edge-triggered latching on CLK rising edge, independent OE-controlled high-impedance outputs, and 24mA drive capability at 3.0V - enabling robust bus driving in mixed-voltage I/O interfaces of notebook and peripheral systems.

For engineers reviewing the 74LVC574AQ20-13 datasheet, 74LVC574AQ20-13 pinout, 74LVC574AQ20-13 application, or 74LVC574AQ20-13 equivalent, key selection criteria include its IOFF-enabled partial power-down support, Schmitt-trigger inputs for noise immunity, ±5.5V-tolerant I/Os, and verified 100MHz max frequency at 3.3V.

Technical Context

This device implements eight independent D-type latches synchronized to the rising edge of CLK, with output state retention unaffected by OE assertion. The 3-state outputs are fully decoupled from internal latch operation, allowing data updates or hold during bus isolation.

Designed for low-voltage mixed-signal environments, it supports 1.65–3.6V VCC while accepting 0–5.5V input levels and delivering rail-to-rail output swing. Its IOFF circuitry ensures negligible leakage (<±10μA) when powered down, meeting JEDEC JESD78 Class I latch-up immunity (>250mA).

Key Specifications

Pinout & Package

V-QFN4525-20 package: 2.5mm × 4.5mm × 0.95mm body, 0.50mm pitch, exposed thermal pad (pin 20), RoHS-compliant, halogen-free "Green" construction.

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 74LVCH16374ADGG, the 74LVC574AQ20-13 delivers superior thermal performance (θJA = 67°C/W), smaller footprint (2.5×4.5mm), and identical electrical specs - making it optimal for space-constrained, thermally demanding embedded designs.

Availability

74LVC574AQ20-13 is available at Aetrix Electronics and suitable for PC notebook I/O expansion, HDD interface buffering, set-top box CEC interfacing, and industrial PLC digital input modules requiring stable component supply across production lifecycles.

Supply support for 74LVC574AQ20-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability, energy-efficient components for computing, consumer, and industrial markets.

The 74LVC logic family targets low-voltage, high-speed digital interfacing - designed specifically for mixed-voltage system integration, bus driving, and I/O expansion in space- and power-constrained applications.

FAQ

Does the 74LVC574AQ20-13 support hot insertion in live backplanes?

Yes - its IOFF circuitry ensures near-zero leakage (<±10μA) when VCC = 0V, and 5.5V-tolerant I/Os prevent damage from floating or pre-charged bus lines. Combined with fast 3-state disable (<10ns), it safely isolates during hot-swap events without requiring external protection.

Can OE be toggled asynchronously while CLK is active without corrupting latch state?

Yes - OE operates independently of the internal latch; asserting or deasserting OE has no effect on stored D-input values or clock synchronization. Data remains retained in the flip-flops regardless of OE state, enabling dynamic bus arbitration without data loss.

What is the minimum VCC required to maintain valid logic levels at the outputs?

The device guarantees functional operation down to 1.65V VCC, with VOH ≥ VCC − 0.2V and VOL ≤ 0.2V under light load. At 1.5V (data retention only), outputs retain state but are not guaranteed to drive external loads - intended solely for low-power hold mode, not active signaling.

How does the Schmitt-trigger input improve noise immunity in noisy industrial environments?

Schmitt-trigger action provides hysteresis (~0.3V typical at 3.3V), raising the input threshold for rising edges and lowering it for falling edges. This prevents multiple toggling from slow-rising or noisy signals - critical for reliable operation on long traces or near motor drivers without added RC filtering.