STMicroelectronics 74VHC174TTR

Overview

74VHC174TTR from STMicroelectronics is a high-speed CMOS hex D-type flip-flop with asynchronous clear, operating from 2V to 5.5V supply, featuring 175MHz max clock frequency (typ. at 5V), 8mA output drive, and pin/function compatibility with standard 74-series 174 devices. It is used in synchronous logic control, data latching, and clock-domain interfacing in industrial controllers and digital instrumentation.

For engineers reviewing the 74VHC174TTR datasheet, 74VHC174TTR pinout, 74VHC174TTR application, or 74VHC174TTR equivalent, key selection criteria include propagation delay symmetry (tPLH ≅ tPHL), input overvoltage tolerance (0–7V independent of VCC), ESD immunity (2kV HBM), and power-down input protection for mixed-voltage system interfacing.

Technical Context

This device implements six edge-triggered D-type flip-flops sharing a common clock and asynchronous active-low clear. Each stage transfers the D-input state to its Q-output on the rising edge of CLOCK, with CLEAR overriding all other inputs to force Q low regardless of clock or data state.

It employs sub-micron C2MOS technology with double-layer metal wiring, enabling rail-to-rail input tolerance, symmetrical output impedance (|IOH| = IOL ≥ 8mA), and balanced propagation delays - critical for timing-critical register banks and pipeline stages in programmable logic interfaces.

Key Specifications

Pinout & Package

TSSOP-16 package: 4.4 mm × 5.0 mm body, 0.65 mm pitch, 1.2 mm height, lead-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74VHC174DT and MC74VHC174DR2G, the 74VHC174TTR offers identical logic performance in a space-saving TSSOP-16 package, optimized for high-density industrial PCBs where thermal profile and reflow compatibility are critical - unlike the SOIC variant, and without requiring automotive qualification overhead.

Availability

74VHC174TTR is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, digital test equipment data capture, and multi-voltage logic level translation requiring stable component supply and long-term manufacturability.

Supply support for 74VHC174TTR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, digital, and mixed-signal ICs for industrial, automotive, and consumer markets.

The 74VHC series targets high-speed, low-power logic applications in industrial control and instrumentation, emphasizing robustness, wide supply range, and interoperability across voltage domains.

FAQ

Can 74VHC174TTR operate reliably at 2.0V supply?

Yes. The device is fully specified down to 2.0V VCC, with guaranteed parameters including fMAX ≥ 80 MHz (min.), VIH ≥ 1.5V, and VOL ≤ 0.55V at 4mA load. Propagation delay increases to ~13ns (typ.), but all DC and AC functions remain valid across the full −55°C to +125°C temperature range.

Is the CLEAR input truly asynchronous and glitch-immune?

Yes. CLEAR is asynchronous, active-low, and internally synchronized only to avoid metastability on deassertion. Its minimum pulse width is 5.0ns (at 5V), and it overrides clock and data unconditionally - verified across all temperature and voltage corners per Table 7 timing specifications.

Does 74VHC174TTR require external pull-up or pull-down resistors on unused inputs?

No. All inputs feature built-in power-down protection and accept 0–7V regardless of VCC. Unused inputs may be left floating without risk of leakage, oscillation, or latch-up - confirmed by absolute maximum ratings (VI = −0.5V to +7.0V) and input equivalent circuit (Figure 2).

What is the maximum capacitive load this device can drive reliably?

The device is characterized up to 50 pF (Table 7), delivering 4.1ns propagation delay (5V, CL=15pF) and 5.5ns (5V, CL=50pF). Driving >50pF risks violating tPLH/tPHL specs and increasing VOLP; for heavier loads, use a dedicated buffer or reduce trace length and capacitance.