Texas Instruments CD74HC273M

Overview

CD74HC273M from Texas Instruments is an octal positive-edge-triggered D-type flip-flop with asynchronous active-low reset, operating from 2V to 6V, delivering 8-bit synchronous data latching for bus interfacing and clock domain synchronization in industrial control and embedded logic systems.

For engineers reviewing the CD74HC273M datasheet, CD74HC273M pinout, CD74HC273M application, or CD74HC273M equivalent, this device supports high-noise-immunity CMOS logic (NIL/NIH = 30% at VCC = 5V), offers 38 ns max propagation delay at 4.5V, and enables stable 8-bit storage across –55°C to +125°C ambient conditions.

Technical Context

The CD74HC273M implements eight independent D-type latches sharing a common clock (CLK) and a single asynchronous clear (CLR) input, with all outputs updated on the rising edge of CLK while CLR forces Q outputs low regardless of clock state. Its silicon-gate CMOS process ensures rail-to-rail output swing and low static current (ICC ≤ 160 μA at 6V over full temperature range).

It features buffered standard CMOS inputs with 10 LSTTL fanout capability, balanced push-pull outputs capable of sourcing/sinking ±25 mA per pin, and input capacitance of 10 pF - enabling reliable operation into 50 pF loads without timing degradation.

Key Specifications

Pinout & Package

DW package: 20-pin SOIC, 12.80 mm × 7.50 mm body, gull-wing leads, JEDEC MS-013 compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC273PW and CD74HCT273M, CD74HC273M uniquely combines wide 2–6 V operation, extended –55°C to +125°C qualification, and full HC-level noise immunity - making it the only option qualified for high-reliability embedded systems requiring both voltage flexibility and environmental ruggedness.

Availability

CD74HC273M is available at Aetrix Electronics and suitable for industrial automation, aerospace avionics, and automotive powertrain control applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74HC273M 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 U.S.-based semiconductor company specializing in analog, embedded processing, and logic solutions, with leadership in high-reliability industrial and automotive-grade components.

The CD74HC273M belongs to TI's CDx4HC(T)273 family of high-speed CMOS octal D-type flip-flops, designed specifically for robust data synchronization, bus buffering, and 8-bit memory functions in harsh-environment digital systems.

FAQ

What is the maximum clock frequency supported by CD74HC273M at 3.3 V supply?

The CD74HC273M datasheet does not specify timing parameters at exactly 3.3 V. However, interpolation from published values shows fMAX = 25 MHz at VCC = 4.5 V and 5 MHz at VCC = 2 V. At 3.3 V, typical maximum clock frequency is approximately 12–15 MHz under CL = 15 pF loading, verified via characterization curves in TI's SCHS174D datasheet. Always validate timing margins in final PCB layout.

Does CD74HC273M support synchronous reset functionality?

No, CD74HC273M implements only asynchronous active-low reset (CLR). The reset function operates independently of the clock signal and forces all Q outputs low immediately upon assertion, regardless of CLK state or edge. There is no provision for synchronous reset or preset in the CD74HC273M design.

Can unused D inputs on CD74HC273M be left floating?

No. All unused D inputs on CD74HC273M must be terminated to either VCC or GND. Floating CMOS inputs cause excessive power consumption, potential oscillation, and reliability degradation. A 10 kΩ pull-up or pull-down resistor is recommended if the input may be driven later; direct connection is acceptable for permanently unused channels.

Is CD74HC273M pin-compatible with CD74HCT273M?

Yes, CD74HC273M and CD74HCT273M share identical DW (SOIC-20) package dimensions, pin numbering, and pin functions - including CLK, CLR, Dn, Qn, VCC, and GND assignments. However, they differ electrically: CD74HC273M operates from 2–6 V with CMOS input thresholds, while CD74HCT273M is 4.5–5.5 V only with TTL-compatible inputs.

What is the purpose of the "buffered inputs" feature listed in CD74HC273M documentation?

Buffered inputs in CD74HC273M refer to internal Schmitt-trigger-like input stage conditioning that improves noise rejection and ensures clean signal transitions into the flip-flop core. This reduces sensitivity to slow-rising edges and external interference, supporting reliable operation in electrically noisy environments such as factory floors or motor drive cabinets where the CD74HC273M is commonly deployed.