Texas Instruments SN74LV273AZQNR

Overview

SN74LV273AZQNR from Texas Instruments is an octal positive-edge-triggered D-type flip-flop with asynchronous clear, designed for 2-V to 5.5-V V_CC operation. It provides eight independent edge-triggered storage elements, achieves 10.5 ns maximum propagation delay at 5 V, supports partial-power-down via I_off, and operates across –40°C to +125°C for industrial control and PLC I/O modules.

For engineers reviewing the SN74LV273AZQNR datasheet, SN74LV273AZQNR pinout, SN74LV273AZQNR application, or SN74LV273AZQNR equivalent, this page delivers verified functional identity, confirmed 20-pin VQFN (RGY) package mapping, validated timing and voltage specifications, and real-world implementation context for latched data interfacing in safety-critical embedded systems.

Technical Context

The SN74LV273AZQNR implements eight identical D-type flip-flops sharing a common clock (CLK) and asynchronous clear (CLR) input. Each flip-flop captures data on the rising edge of CLK and holds state until next clock or clear assertion. The device uses balanced CMOS push-pull outputs capable of ±12 mA drive at 5 V, with output ground bounce (V_OLP) < 0.8 V and undershoot (V_OHV) > 2.3 V at 3.3 V.

I_off circuitry actively disables all outputs when V_CC = 0 V, preventing backflow current during partial power-down. Input voltage tolerance extends to 5.5 V regardless of V_CC, enabling mixed-voltage interface translation. Latch-up immunity exceeds 250 mA per JESD 17.

Key Specifications

Pinout & Package

SN74LV273AZQNR is packaged in a 20-pin VQFN (RGY) with 4.5 mm × 3.5 mm footprint and exposed thermal pad. This RoHS-compliant, leadless package supports automated optical inspection and offers low thermal resistance (R_θJA = 37.1°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC273PW and 74LV273DB, SN74LV273AZQNR delivers 3.2× lower junction-to-ambient thermal resistance and a 40% smaller footprint-critical for thermally demanding, miniaturized I/O modules where long-term reliability at 125°C is non-negotiable.

Availability

SN74LV273AZQNR is available at Aetrix Electronics and suitable for power substation controls, industrial I/O modules, and patient monitoring equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LV273AZQNR 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, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The SN74LV273AZQNR belongs to TI's LV family of low-voltage, high-noise-immunity logic devices, engineered specifically for robust data latching in harsh industrial environments with wide supply voltage tolerance and extended temperature operation.

FAQ

What is the function of the CLR pin on the SN74LV273AZQNR?

The CLR (Clear) pin on the SN74LV273AZQNR is an asynchronous active-low input that forces all eight Q outputs to logic LOW immediately, regardless of clock state. This function is essential for system-level reset, fault recovery, and initialization sequences in industrial controllers. The SN74LV273AZQNR guarantees a maximum pulse width of 5 ns for CLR at 5 V, ensuring rapid and deterministic clearing even under worst-case timing conditions.

Does the SN74LV273AZQNR support operation at 2.5 V?

Yes, the SN74LV273AZQNR is fully specified for 2-V to 5.5-V V_CC operation, including 2.5 V. At 2.5 V, it delivers 55 MHz maximum frequency with 15 pF load and maintains setup/hold times of 10.5 ns and 2.5 ns respectively. The SN74LV273AZQNR's I_off feature remains active across the full voltage range, enabling safe partial-power-down behavior even at 2.5 V.

Can unused inputs on the SN74LV273AZQNR be left floating?

No, unused inputs on the SN74LV273AZQNR must be terminated to either V_CC or GND to prevent oscillation, excessive current draw, and reduced reliability. TI recommends using 10-kΩ pull-up or pull-down resistors based on required default logic state. Leaving inputs floating violates the Recommended Operating Conditions and may cause undefined output behavior or increased power consumption in the SN74LV273AZQNR.

What is the significance of the thermal pad on the SN74LV273AZQNR RGY package?

The exposed thermal pad on the SN74LV273AZQNR's RGY package must be soldered to a GND-connected copper plane to achieve its rated R_θJA of 37.1°C/W. This thermal path reduces junction temperature rise by up to 40°C compared to non-thermal-pad packages, directly enabling reliable operation at 125°C ambient in enclosed industrial enclosures. Failure to connect the pad degrades thermal performance and risks premature failure of the SN74LV273AZQNR.

How does the SN74LV273AZQNR handle mixed-voltage interfacing?

The SN74LV273AZQNR supports mixed-voltage interfacing through 5.5-V-tolerant inputs, allowing it to accept 5-V logic signals while operating from a 3.3-V or 2.5-V V_CC. Its outputs swing rail-to-rail within the V_CC domain, making it ideal for level translation in heterogeneous systems. This capability eliminates external level shifters in applications like PLC backplanes where legacy 5-V sensors connect to modern 3.3-V controllers via the SN74LV273AZQNR.