Texas Instruments SN74LV74APW

Overview

SN74LV74APW from Texas Instruments is a dual positive-edge-triggered D-type flip-flop IC designed for 2-V to 5.5-V operation, featuring 8.5 ns maximum propagation delay at 5 V, I_off partial-power-down support, and mixed-mode voltage operation across all ports. It serves as a synchronous storage element in digital control logic, clock domain interfacing, and state-holding circuits within industrial PLCs and server motherboard timing subsystems.

For engineers reviewing the SN74LV74APW datasheet, SN74LV74APW pinout, SN74LV74APW application, or SN74LV74APW equivalent, key selection criteria include its 14-pin TSSOP package, dual independent flip-flop architecture with asynchronous preset/clear, guaranteed operation down to 2 V, and compatibility with 3.3-V and 5-V logic systems without level shifters.

Technical Context

This device implements two identical, independent D-type flip-flops, each with separate asynchronous active-low preset (PRE) and clear (CLR) inputs, a single data (D) input, a positive-edge-triggered clock (CLK), and complementary Q and Q outputs. Its I_off circuitry disables outputs during power-down to prevent backflow current, and its overvoltage-tolerant inputs accept up to 5.5 V regardless of V_CC level.

The SN74LV74APW operates across –40°C to +125°C, supports load capacitances up to 50 pF, and delivers rail-to-rail output swing (V_OH ≥ 3.8 V at V_CC = 4.5 V, V_OL ≤ 0.55 V at same condition). Timing parameters are fully characterized at 2.5 V, 3.3 V, and 5 V supply voltages, with minimum pulse width requirements of 5 ns on CLK and PRE/CLR at 5 V.

Key Specifications

Pinout & Package

TSSOP-14 (PW) package, 5.00 mm × 4.40 mm body size, 0.65 mm lead pitch, surface-mount, RoHS-compliant with NiPdAu or Sn lead finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC74APW and 74AHC74PW, the SN74LV74APW uniquely balances wide supply range (2–5.5 V), input overvoltage tolerance, and I_off protection-making it the only option among the three qualified for mixed-domain industrial control where power sequencing and bus interoperability are mandatory.

Availability

SN74LV74APW is available at Aetrix Electronics and suitable for programmable logic controllers, server motherboards, and distributed control systems requiring stable component supply across extended temperature ranges and multi-voltage architectures.

Supply support for SN74LV74APW 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, with decades of experience in high-reliability industrial and automotive-grade components.

The SN74LV74A product line delivers low-voltage, high-noise-immunity logic devices optimized for industrial automation, communications infrastructure, and computing platforms demanding robust timing behavior and mixed-voltage interoperability.

FAQ

What is the supply voltage range supported by the SN74LV74APW?

The SN74LV74APW supports a V_CC range of 2 V to 5.5 V, enabling operation across 2.5-V, 3.3-V, and 5-V logic families. This wide range allows the SN74LV74APW to interface directly with mixed-voltage systems without external level shifters, and its inputs tolerate up to 5.5 V regardless of applied V_CC, making it ideal for down-translation applications.

Does the SN74LV74APW support partial-power-down operation?

Yes, the SN74LV74APW includes I_off circuitry that disables outputs when V_CC = 0 V, preventing damaging current backflow during power sequencing or hot-swap events. This feature is explicitly specified in the datasheet with I_off ≤ 5 µA at 3.3 V, confirming its suitability for systems requiring robust partial-power-down behavior.

What are the timing requirements for the clock input of the SN74LV74APW?

The SN74LV74APW requires a minimum clock pulse width (t_w) of 5 ns at V_CC = 5 V, 6 ns at 3.3 V, and 8 ns at 2.5 V. Setup time (t_su) is 3 ns at 5 V, 5 ns at 3.3 V, and 7 ns at 2.5 V; hold time (t_h) is consistently 0.5 ns across all supply voltages. These values are measured under standard load conditions (CL = 15 pF or 50 pF) and define the minimum valid clock window for reliable state capture.

How does the SN74LV74APW handle asynchronous preset and clear functions?

The SN74LV74APW features dedicated active-low asynchronous inputs (1PRE, 1CLR, 2PRE, 2CLR) that force immediate state changes independent of the clock. When asserted, PRE sets Q = H / Q = L and CLR sets Q = L / Q = H for their respective flip-flops. These overrides take priority over clock and data, and the function table confirms stable outputs even during simultaneous PRE/CLR assertion (though this state is non-persistent upon deassertion).

Is the SN74LV74APW pin-compatible with other 74-series dual D-type flip-flops?

The SN74LV74APW uses the industry-standard 14-pin TSSOP (PW) footprint and matches the pinout of SN74LV74A variants in SOIC, SSOP, TVSOP, and VQFN packages. However, it is not pin-compatible with non-LV families (e.g., 74HC74, 74AHC74) due to differing input threshold definitions and drive strength. Always verify voltage compatibility and timing margins before substitution.