Texas Instruments SN74LV174APW

Overview

SN74LV174APW from Texas Instruments is a hex D-type positive-edge-triggered flip-flop with asynchronous clear, designed for 2 V to 5.5 V operation, featuring 7.5 ns maximum propagation delay at 5 V, Ioff support for partial-power-down mode, and mixed-mode voltage interface capability on all ports. It serves as a synchronous data latch in digital control logic, LED matrix drivers, and 7-segment display interfaces.

For engineers reviewing the SN74LV174APW datasheet, SN74LV174APW pinout, SN74LV174APW application, or SN74LV174APW equivalent, key selection criteria include its 16-pin TSSOP package, guaranteed tpd ≤ 7.5 ns at 5 V, VCC range spanning 2–5.5 V, Ioff leakage < 5 µA at 0 V supply, and compatibility with 5-V-tolerant inputs for level translation.

Technical Context

The SN74LV174APW implements six independent D-type latches triggered on the rising edge of CLK, each with dedicated D input and Q output, plus a shared active-low asynchronous CLR that forces all Q outputs low regardless of clock state. Its CMOS push-pull outputs provide balanced sourcing/sinking (±12 mA at 4.5–5.5 V), enabling direct drive of light loads without external buffers.

It supports partial-power-down via Ioff circuitry that disables all outputs when VCC = 0 V, limiting leakage to ≤5 µA per terminal. Input thresholds scale with VCC (VIH = 0.7×VCC, VIL = 0.3×VCC), ensuring robust noise margins across the full 2–5.5 V supply range and enabling interoperability between 3.3 V logic domains and 5 V systems.

Key Specifications

Pinout & Package

TSSOP-16 (PW) package: 5.00 mm × 4.40 mm body, 0.65 mm pitch, 1.2 mm max height, RoHS-compliant NiPdAu/Sn lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV174APWR, the SN74LV174APW shares identical functionality but lacks volume production support; versus 74LVC174PW, it trades speed and low-voltage operation for universal 5-V input tolerance and broader supply flexibility - making SN74LV174APW optimal for mixed-voltage industrial control where robustness trumps peak frequency.

Availability

SN74LV174APW is available at Aetrix Electronics and suitable for industrial I/O expansion, LED matrix control, 7-segment display interfaces, and programmable logic glue requiring stable component supply across extended temperature ranges.

Supply support for SN74LV174APW 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 U.S.-based semiconductor company specializing in analog, embedded processing, and logic solutions, with decades of leadership in industrial-grade logic families.

The SN74LV174A product line delivers low-voltage, high-noise-immunity D-type flip-flops optimized for reliable operation in mixed-signal industrial control, display subsystems, and interface bridging applications.

FAQ

What is the maximum clock frequency supported by SN74LV174APW?

The SN74LV174APW supports up to 110 MHz maximum operating frequency (fmax) when loaded with 15 pF and operated at VCC = 5 V, as specified in Section 6.9 of the datasheet. At VCC = 3.3 V and CL = 15 pF, fmax is 170 MHz. These values assume proper layout, decoupling, and signal integrity - actual system-level frequency may be lower due to board parasitics and load conditions. The SN74LV174APW's 7.5 ns maximum tpd at 5 V enables reliable use in 25+ MHz synchronous designs.

Does SN74LV174APW support 5-V-tolerant inputs when powered from 3.3 V?

Yes, SN74LV174APW supports 5-V-tolerant inputs across its full operating range (2 V to 5.5 V). When powered from 3.3 V, all inputs accept VI up to 5.5 V without damage or clamping, enabling direct connection to 5 V microcontrollers, sensors, or legacy logic. This feature is explicitly confirmed in Section 9.1 ("Application Information") and Table 6.1 (Absolute Maximum Ratings), where VI max = 7 V - exceeding 5 V by margin.

What is the purpose of the Ioff feature in SN74LV174APW?

The Ioff feature in SN74LV174APW disables all outputs and limits leakage current to ≤5 µA when VCC = 0 V, preventing back-driving of powered sections during hot-swap, partial power-down, or multi-rail sequencing. This behavior is verified in Section 6.5 (Electrical Characteristics) and Section 8.3.3 (Feature Description), and is critical for system-level power management in industrial and telecom equipment where rail sequencing must avoid contention.

Can SN74LV174APW drive LEDs directly without current-limiting resistors?

No, SN74LV174APW cannot safely drive LEDs without external current-limiting resistors. While its outputs support ±12 mA at 5 V (Section 6.3), continuous DC current must remain within absolute max ratings (±25 mA per output, Section 6.1), and thermal limits require derating under sustained load. Each LED branch requires a series resistor calculated for target current and forward voltage - e.g., 330 Ω for 10 mA at 3.3 V with 1.8 V LED VF. The SN74LV174APW provides drive capability, not current regulation.

Is SN74LV174APW pin-compatible with older 74LS174 or 74HC174 devices?

No, SN74LV174APW is not pin-compatible with 74LS174 (SOIC-16 but different pin mapping) or 74HC174 (same function but distinct pinout: e.g., 74HC174 places CLR on Pin 1, CLK on Pin 10, whereas SN74LV174APW places CLR on Pin 1 and CLK on Pin 9). The SN74LV174APW follows TI's LV logic pinout convention documented in Figure 5-1 and Table 5-1 - substitution requires PCB layout revision. Always verify against the specific package drawing (PW) before replacement.