Texas Instruments SN74AHC273PW

Overview

SN74AHC273PW from Texas Instruments is an octal positive-edge-triggered D-type flip-flop with asynchronous clear, operating from 2 V to 5.5 V. It features eight independent data inputs (1D–8D), eight complementary outputs (1Q–8Q), a shared clock (CLK), and a direct active-low clear (CLR). Used in digital storage and synchronization circuits, it supports voltage translation from 5-V logic to 3.3-V systems.

For engineers reviewing the SN74AHC273PW datasheet, SN74AHC273PW pinout, SN74AHC273PW application, or SN74AHC273PW equivalent, key selection criteria include its 20-pin TSSOP package, 5.5-V tolerant inputs, 100 MHz max frequency at 5 V, ±25 mA output drive, and operation across –40°C to +125°C.

Technical Context

This device implements eight independent D-type latches synchronized to the rising edge of CLK, with asynchronous reset via CLR. Each flip-flop transfers data from D to Q only on CLK's positive transition; no state change occurs during high/low CLK levels.

Its CMOS AHC-family architecture delivers rail-to-rail output swing, low dynamic power consumption (31 pF typical Cpd), and robust noise immunity-supported by 2000-V HBM ESD rating and latch-up immunity exceeding 250 mA per JESD17.

Key Specifications

Pinout & Package

The SN74AHC273PW is housed in a 20-pin Thin Shrink Small Outline Package (TSSOP) with 0.65 mm pitch, body size 6.50 mm × 4.40 mm, and nominal footprint 6.50 mm × 6.40 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74AHCT273PW and 74LVC273PW, the SN74AHC273PW provides the widest supply range (2–5.5 V) and best balance of 5-V tolerance, industrial temperature support, and low-power CMOS efficiency - making it optimal for flexible mixed-voltage industrial control modules.

Availability

SN74AHC273PW is available at Aetrix Electronics and suitable for industrial control systems, embedded memory interfaces, and programmable logic support circuits requiring stable component supply and long-term lifecycle assurance.

Supply support for SN74AHC273PW 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 ICs with over 90 years of innovation in industrial, automotive, and communications markets.

The SN74AHC273PW belongs to TI's advanced high-speed CMOS (AHC) logic family, designed for low-power, high-noise-immunity digital interfacing and data synchronization in mixed-voltage systems.

FAQ

What is the maximum clock frequency supported by the SN74AHC273PW?

The SN74AHC273PW supports up to 100 MHz at VCC = 5 V ± 0.5 V with CL = 15 pF load, as specified in Section 5.9 of the datasheet. At 3.3 V, maximum frequency drops to 65 MHz. These values assume proper layout, bypassing, and signal integrity - actual system performance depends on PCB trace impedance and capacitive loading.

Does the SN74AHC273PW support 5-V input signals when powered from 3.3 V?

Yes, the SN74AHC273PW features 5.5-V tolerant inputs, meaning all D, CLK, and CLR pins accept voltages up to 5.5 V regardless of VCC setting. This allows safe interfacing with 5-V microcontrollers or FPGAs while the SN74AHC273PW operates from a 3.3-V supply - a key feature for voltage translation in mixed-signal systems.

What is the function of the CLR pin on the SN74AHC273PW?

The CLR pin on the SN74AHC273PW is an asynchronous active-low clear input. When pulled low, it forces all eight Q outputs to logic low immediately - independent of the clock signal. This enables deterministic system reset, initialization, or fault recovery without waiting for the next CLK edge, which is essential in safety-critical or real-time control applications.

Can unused inputs on the SN74AHC273PW be left floating?

No, unused inputs on the SN74AHC273PW must not be left floating. All unused D inputs should be tied to either VCC or GND to prevent undefined logic states, increased power consumption, and potential oscillation. TI's application report SCBA004 explicitly warns against floating CMOS inputs due to susceptibility to noise and unintended switching - proper biasing ensures stable and predictable operation of the SN74AHC273PW.

Is the SN74AHC273PW RoHS compliant and lead-free?

Yes, the SN74AHC273PW is RoHS compliant and features a lead-free NIPDAU (nickel/palladium/gold) terminal finish. Per TI's Packaging Information Addendum, the active orderable variant SN74AHC273PWR.A carries RoHS "Yes" status, Level-1 MSL rating, and peak reflow compatibility up to 260°C - confirming full compliance with EU Directive 2011/65/EU and related environmental standards for the SN74AHC273PW family.