Texas Instruments SN74LV574AGQNR

Overview

SN74LV574AGQNR from Texas Instruments is an octal edge-triggered D-type flip-flop with 3-state outputs, designed for 2-V to 5.5-V V_CC operation. It features a maximum propagation delay of 7.1 ns at 5 V, I_off support for partial-power-down mode, and balanced CMOS 3-state outputs optimized for bus interfacing in LED displays and network switches.

For engineers reviewing the SN74LV574AGQNR datasheet, SN74LV574AGQNR pinout, SN74LV574AGQNR application, or SN74LV574AGQNR equivalent, key selection criteria include its 20-pin VQFN (RGY) package, 3.3-V/5-V mixed-mode voltage compatibility, t_su/t_h timing margins at industrial temperature range (–40°C to 125°C), and latch-up immunity exceeding 250 mA per JESD17.

Technical Context

The SN74LV574AGQNR implements positive-edge-triggered latching logic synchronized to CLK, with independent D-input sampling and Q-output registration on each of eight channels. Its buffered output-enable (OE) input controls all eight outputs simultaneously into high-impedance state without affecting internal flip-flop states.

It integrates I_off circuitry that disables outputs during power-down, preventing backflow current when V_CC = 0 V, and uses balanced CMOS 3-state drivers capable of sourcing/sinking up to ±16 mA at 5 V while maintaining low ground bounce (<0.8 V) and undershoot (>2.3 V) at 3.3 V.

Key Specifications

Pinout & Package

SN74LV574AGQNR is packaged in a 20-pin VQFN (RGY) with 4 mm × 3.5 mm body size, exposed thermal pad, and 0.5-mm pitch. The package supports reflow soldering per JEDEC Level-2 moisture sensitivity rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC574APWR and 74AVC8T245, the SN74LV574AGQNR uniquely combines industrial temperature support (–40°C to 125°C), I_off-enabled power sequencing, and guaranteed 7.1-ns t_pd at 5 V - making it optimal for mission-critical buffer registers in telecom and motor control where reliability under thermal stress and safe power-down are mandatory.

Availability

SN74LV574AGQNR is available at Aetrix Electronics and suitable for LED displays, network switches, and telecom infrastructure requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LV574AGQNR 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing solutions, with decades of experience in logic IC design and industrial-grade reliability validation.

The SN74LV574AGQNR belongs to TI's LV-A series of low-voltage, high-speed logic devices engineered for robust bus interface applications in networking, industrial automation, and communications infrastructure.

FAQ

What is the maximum clock frequency supported by SN74LV574AGQNR at 3.3 V?

The SN74LV574AGQNR supports a maximum clock frequency of 145 MHz at V_CC = 3.3 V with C_L = 15 pF, and 120 MHz with C_L = 50 pF. These values derive from measured t_pd and timing margins in TI's SCLS412K datasheet, ensuring reliable edge-triggered operation under typical load conditions. The SN74LV574AGQNR maintains timing integrity across –40°C to 125°C ambient temperatures.

Does SN74LV574AGQNR support 5-V tolerant inputs?

Yes, SN74LV574AGQNR features 5-V tolerant inputs - all D, CLK, and OE pins accept input voltages up to 5.5 V regardless of V_CC level (2 V to 5.5 V). This allows direct interfacing with legacy 5-V logic while operating from lower V_CC rails such as 3.3 V or 2.5 V, eliminating level-shifter components in mixed-voltage systems using SN74LV574AGQNR.

How does the I_off feature function in SN74LV574AGQNR?

The I_off circuitry in SN74LV574AGQNR automatically disables all outputs when V_CC is at 0 V, limiting leakage current to ≤5 µA per pin. This prevents damaging backflow current from live buses into unpowered sections of a system. The SN74LV574AGQNR retains this behavior across its full operating temperature range and is verified per JESD78 latch-up testing standards.

What is the thermal resistance (R_θJA) of SN74LV574AGQNR in its RGY package?

The SN74LV574AGQNR in the 20-pin VQFN (RGY) package has a junction-to-ambient thermal resistance (R_θJA) of 37°C/W, as specified in TI's SCLS412K datasheet. This value assumes standard JEDEC 2-layer board layout with 1-in² copper pour under the exposed thermal pad. The low R_θJA enables reliable operation at full drive strength up to 125°C ambient without derating.

Can SN74LV574AGQNR replace older SN74LS574 devices in existing designs?

SN74LV574AGQNR is not a direct drop-in replacement for SN74LS574 due to differences in logic family (TTL vs. LV-CMOS), supply voltage (4.75–5.25 V vs. 2–5.5 V), and output drive architecture. While functional equivalence exists for basic latching, SN74LV574AGQNR requires validation of timing margins, bus loading, and power sequencing. The SN74LV574AGQNR offers superior noise immunity and lower power but needs updated layout for its VQFN thermal pad and decoupling.