Texas Instruments SN74HC273DW

Overview

SN74HC273DW from Texas Instruments is an octal positive-edge-triggered D-type flip-flop with active-low asynchronous clear, operating across 2 V to 6 V supply. It delivers ±4 mA output drive at 5 V, 12 ns typical propagation delay, and 80 µA maximum ICC, used in synchronous data latching and register storage within industrial control logic and digital instrumentation.

For engineers reviewing the SN74HC273DW datasheet, SN74HC273DW pinout, SN74HC273DW application, or SN74HC273DW equivalent, key selection criteria include its SOIC-20 package, single-rail outputs, direct clear functionality, and compatibility with LSTTL loads in clock-synchronized state-holding circuits.

Technical Context

The SN74HC273DW implements eight independent D flip-flops sharing a common clock (CLK) and global active-low clear (CLR) input. Each flip-flop captures data on the rising edge of CLK while CLR forces all Q outputs low regardless of clock or data state.

Its CMOS design ensures rail-to-rail input thresholds (VIH = 3.15 V, VIL = 1.35 V at VCC = 4.5 V), 100 ns minimum setup time at 4.5 V, and guaranteed operation from –40°C to +85°C - making it suitable for noise-immune, medium-speed digital interfacing where deterministic edge-triggered storage is required.

Key Specifications

Pinout & Package

SN74HC273DW is housed in a 20-pin SOIC (DW) package measuring 12.80 mm × 7.50 mm, with standard 1.27 mm pitch and gull-wing leads compatible with reflow soldering per Level-1 MSL rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC374DW and 74ACT273SC, the SN74HC273DW provides optimal balance of supply voltage range, power efficiency, and pinout simplicity for fixed-output register applications - especially where 2–6 V operation or minimal quiescent current is prioritized over tri-state capability or raw speed.

Availability

SN74HC273DW is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, digital test equipment register banks, and microcontroller peripheral interface applications requiring stable component supply and long-term production continuity.

Supply support for SN74HC273DW 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 decades of heritage in industry-standard logic families.

The SN74HC273DW belongs to TI's HC (High-Speed CMOS) logic series, designed for low-power, wide-supply-voltage digital interfacing in industrial, automotive, and communications systems.

FAQ

What is the operating temperature range for SN74HC273DW?

The SN74HC273DW is rated for operation from –40°C to +85°C, meeting industrial temperature requirements. This range is confirmed in Section 6.3 Recommended Operating Conditions of the official TI datasheet (SCLS136F), and applies specifically to the DW (SOIC) package variant. The device maintains full electrical performance across this span without derating.

Does SN74HC273DW support 3.3 V logic levels?

Yes, SN74HC273DW fully supports 3.3 V operation: its recommended supply range is 2 V to 6 V, and input thresholds scale with VCC (e.g., VIH = 2.31 V min at VCC = 3.3 V). Output VOH/VOL specifications guarantee compatibility with 3.3 V LVTTL and LVCMOS interfaces, as verified in Table 6.7 Electrical Characteristics – SN74HC273.

Is SN74HC273DW pin-compatible with SN74HC374DW?

No, SN74HC273DW is not pin-compatible with SN74HC374DW. While both are 20-pin SOIC octal D flip-flops, SN74HC374DW replaces the dedicated CLR pin (Pin 1) with an output-enable (OE) pin and relocates Q outputs - resulting in different pin functions and incompatible PCB layouts. Refer to TI's Pin Configuration tables (Section 5) for exact mapping.

What is the maximum clock frequency supported by SN74HC273DW?

At VCC = 4.5 V, SN74HC273DW supports a maximum clock frequency of 21 MHz under recommended operating conditions (Section 6.10). This is derived from minimum pulse width (20 ns high/low) and setup/hold timing constraints. At 6 V, max fclock rises to 25 MHz; at 2 V, it drops to 4 MHz - all specified in the SN74HC273 timing tables.

Can unused inputs on SN74HC273DW be left floating?

No, unused inputs on SN74HC273DW must not be left floating. As stated in Section 11.1 Layout Guidelines, all unused inputs must be tied to VCC or GND to prevent undefined logic states, increased power consumption, or oscillation. This requirement is due to CMOS input structure sensitivity - TI explicitly warns against floating inputs in the datasheet and recommends pull-up/pull-down resistors where appropriate.