STMicroelectronics 74VHC273TTR

Overview

74VHC273TTR from STMicroelectronics is an octal D-type flip-flop with asynchronous clear, designed for high-speed synchronous data latching in 2–5.5 V logic systems. It features 165 MHz max clock frequency (5 V), 8 mA output drive, ±25 mA DC output current, and operates across –55°C to +125°C. Used in address/data register buffering, state machine control, and clock-domain synchronization in industrial PLCs and instrumentation.

For engineers reviewing the 74VHC273TTR datasheet, 74VHC273TTR pinout, 74VHC273TTR application, or 74VHC273TTR equivalent, key selection criteria include propagation delay matching (tPLH/tPHL ≤ 10.5 ns at 5 V), input voltage tolerance (0–7 V independent of VCC), ESD immunity (2 kV HBM), and TSSOP-20 package compatibility with 3.3 V/5 V mixed-signal interfaces.

Technical Context

The 74VHC273TTR implements eight edge-triggered D flip-flops sharing a common clock and asynchronous active-low clear. Its C2MOS process enables rail-to-rail input tolerance and power-down protection-inputs accept 0–7 V regardless of VCC, preventing latch-up during hot insertion or supply sequencing.

All outputs exhibit symmetrical drive strength (|IOH| = IOL ≥ 8 mA) and balanced propagation delays (tPLH ≅ tPHL), supporting clean timing margins in multi-bit register chains. The device supports dual-supply interfacing (e.g., 5 V logic driving 3.3 V loads) without external level shifters due to overvoltage-tolerant inputs and low-noise outputs (VOLP ≤ 0.9 V).

Key Specifications

Pinout & Package

TSSOP-20 package: 6.5 mm × 4.4 mm body, 0.65 mm pitch, 1.05 mm max height, lead-free and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV273APW and MC74VHC273DT, the 74VHC273TTR uniquely combines 5 V speed headroom, universal input voltage tolerance, and TSSOP-20 miniaturization-making it optimal for mixed-voltage industrial controllers requiring field-replaceable reliability.

Availability

74VHC273TTR is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, test equipment design, and medical device control systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74VHC273TTR 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, Switzerland, delivering silicon solutions for smart mobility, power, and sensing applications since 1987.

The 74VHC logic family targets high-speed, low-power, and robust interface functions in industrial, automotive, and instrumentation systems-designed specifically for reliable operation under voltage transients, wide temperature swings, and mixed-supply environments.

FAQ

Can the 74VHC273TTR operate with VCC = 3.3 V while accepting 5 V signals on D inputs?

Yes. Its inputs tolerate 0–7 V regardless of VCC, enabling direct connection of 5 V sensors or legacy peripherals to a 3.3 V-powered 74VHC273TTR. No external level shifters or resistive dividers are needed, and the internal protection circuitry prevents latch-up or damage under these conditions.

What is the minimum pulse width required on the CLEAR input to ensure reliable reset?

The minimum CLEAR pulse width is 5.0 ns at VCC = 5.0 V (per AC specs). At VCC = 3.3 V, it is 6.0 ns. This ensures full propagation through internal logic stages and guarantees all eight Q outputs reach logic low before the next clock edge, even under worst-case process/voltage/temperature corners.

Does the 74VHC273TTR require external pull-up or pull-down resistors on unused inputs?

No. All inputs feature built-in power-down protection and high-impedance behavior when unconnected. However, for EMI reduction and noise immunity in noisy environments, STMicroelectronics recommends tying unused D inputs to GND or VCC via 10 kΩ resistors-not left floating-to avoid unintended state changes during electromagnetic interference events.

How does the 74VHC273TTR handle simultaneous switching of all eight outputs?

Simultaneous switching induces ground bounce (VOLP ≤ 0.9 V at CL = 50 pF) and supply droop. The device's symmetrical output impedance and low CPD (31 pF) limit transient current demand. For full 8-bit switching, ST recommends local 100 nF ceramic decoupling within 5 mm of VCC/GND pins and separation of digital/analog ground planes to maintain signal integrity.