onsemi 74ACTQ273SJX

Overview

74ACTQ273SJX from Fairchild Semiconductor is an octal D-type edge-triggered flip-flop with buffered common clock (CP) and asynchronous master reset (MR), 8-bit parallel data storage, 24 mA output drive, and Quiet Series™ noise suppression. It operates at 4.5–5.5 V over −40°C to +85°C and delivers 110 MHz max clock frequency in industrial environments - used in synchronous bus interfaces and digital control registers where deterministic timing and low simultaneous switching noise are critical.

For engineers reviewing the 74ACTQ273SJX datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed pin-to-pin skew ≤1.0 ns, dynamic VOLP ≤1.5 V (quiet output), VIHD ≥2.2 V and VILD ≤0.8 V for noise-immune input thresholds, and MR-synchronized reset behavior across all eight outputs.

Technical Context

The 74ACTQ273SJX implements fully edge-triggered D-flip-flop logic with setup time (t_S) of 3.5 ns and hold time (t_H) of 1.5 ns at 5.0 V, ensuring reliable sampling of D0–D7 inputs on the LOW-to-HIGH CP transition. Its asynchronous MR input forces all Q0–Q7 outputs LOW independently of clock or data state.

It integrates Fairchild's Quiet Series™ technology featuring GTO™ output control, undershoot correction, and split ground bus architecture - delivering 50% reduced I_CC, 4 kV ESD immunity, and guaranteed simultaneous switching noise performance validated per FACT Noise Characteristics test methodology using 1 MHz toggling and 50 pF load.

Key Specifications

Pinout & Package

74ACTQ273SJX is packaged in a 20-lead Small Outline Package (SOP), EIAJ TYPE II, 5.3 mm wide (Package Number M20D), with gull-wing leads and standard JEDEC footprint compatibility.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74ACTQ273SJX, the 74ACT273SCX trades noise suppression for lower unit cost and broader distributor availability, while the SN74ACT273N offers identical logic functionality in PDIP but forfeits quiet-output guarantees and surface-mount flexibility - making 74ACTQ273SJX optimal for noise-critical, space-constrained industrial PCBs.

Availability

74ACTQ273SJX is available at Aetrix Electronics and suitable for industrial bus interface, digital control register, test equipment data capture, and communications frame buffer applications requiring stable component supply, long-term lifecycle support, and consistent parametric performance across temperature extremes.

Supply support for 74ACTQ273SJX 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

Fairchild Semiconductor was a U.S.-based semiconductor company specializing in analog and mixed-signal ICs, power management, and logic families before its acquisition by ON Semiconductor in 2016.

The 74ACTQ273SJX belongs to Fairchild's ACT Quiet Series™ logic family, engineered specifically for industrial and instrumentation systems demanding ultra-low switching noise, high noise immunity, and deterministic timing under heavy capacitive loading.

FAQ

What is the maximum operating temperature range for the 74ACTQ273SJX?

The 74ACTQ273SJX is rated for operation from −40°C to +85°C, meeting industrial temperature requirements. This range is verified across all AC and DC specifications including propagation delay, setup/hold times, and output drive capability - ensuring reliable performance in factory automation, motor control, and outdoor instrumentation environments where ambient temperatures fluctuate widely. The 74ACTQ273SJX maintains full functionality without derating within this range.

Does the 74ACTQ273SJX support true pin-to-pin compatibility with standard 74ACT273 devices?

The 74ACTQ273SJX shares identical pinout, logic function, and DC/AC electrical specifications with non-Quiet Series 74ACT273 variants, including 74ACT273SCX and SN74ACT273N. However, it adds Quiet Series™ enhancements - GTO™ output control and undershoot correction - which do not alter pin assignment or basic timing behavior. The 74ACTQ273SJX can be substituted in existing 74ACT273 layouts without modification, though its noise-suppression benefits require proper decoupling and grounding per Fairchild's layout guidelines.

What is the purpose of the VOLP and VOLV parameters specified for the 74ACTQ273SJX?

VOLP (Quiet Output Maximum Dynamic VOL) and VOLV (Quiet Output Minimum Dynamic VOL) characterize worst-case output voltage excursions during simultaneous switching events - VOLP ≤1.5 V and VOLV ≥−1.2 V at V_CC = 5.0 V. These parameters quantify the effectiveness of the 74ACTQ273SJX's Quiet Series™ noise suppression, ensuring that output glitches remain within safe margins relative to downstream input thresholds. They are measured per Fairchild's FACT Noise Characteristics test procedure and are critical for validating signal integrity in dense, high-speed PCB layouts.

How does the Master Reset (MR) input behave in the 74ACTQ273SJX?

The MR input of the 74ACTQ273SJX is active-LOW and asynchronous: asserting MR = LOW forces all Q0–Q7 outputs immediately LOW, independent of clock state or D-input values. This reset overrides all internal flip-flop states and remains effective even if CP is static or floating. Release of MR (transition to HIGH) does not trigger a clock event - the 74ACTQ273SJX resumes normal edge-triggered operation only on the next valid LOW-to-HIGH CP transition. This behavior makes the 74ACTQ273SJX ideal for system-level initialization sequences.

Is the 74ACTQ273SJX RoHS compliant and lead-free?

The 74ACTQ273SJX was originally manufactured by Fairchild Semiconductor prior to its 2016 acquisition by ON Semiconductor and predates mandatory RoHS compliance for legacy logic families. While the device meets JEDEC MS-013 mechanical standards and operates reliably in industrial environments, it is not certified RoHS-compliant or lead-free. For new designs requiring RoHS compliance, engineers should consult ON Semiconductor's current-generation ACT-compatible alternatives or verify material declarations through authorized distributors' traceability records for specific date-code batches.