Texas Instruments CD74HC73M

Overview

CD74HC73M from Texas Instruments is a dual J-K flip-flop with asynchronous reset, negative-edge clock triggering, complementary Q/Q̅ outputs, and buffered inputs - designed for synchronous logic control in digital systems operating from 2 V to 6 V. It delivers 60 MHz maximum clock frequency at 5 V/15 pF, supports –55°C to +125°C industrial/military temperature range, and drives up to 10 LSTTL loads.

For engineers reviewing the CD74HC73M datasheet, CD74HC73M pinout, CD74HC73M application, or CD74HC73M equivalent, this page provides verified functional identity, SOIC-14 package mapping, timing parameters (tPLH/tPHL ≤ 41 ns @ 6 V), noise-immune hysteresis on clock inputs, and validated alternatives for logic-level-compatible J-K flip-flop replacement.

Technical Context

The CD74HC73M implements two independent edge-triggered J-K flip-flops in a single silicon-gate CMOS IC, each with dedicated J, K, CLK, and asynchronous RESET inputs plus true/complement outputs. Its negative-edge-triggered operation ensures state changes only on high-to-low clock transitions, while hysteresis on CLK inputs improves noise immunity and accommodates slower input rise/fall times.

All logic functions conform to HC-type specifications: 2–6 V supply range, VIH/VIL thresholds scalable with VCC (e.g., VIH = 4.2 V min @ 6 V), and guaranteed fanout of 10 LSTTL loads across the full temperature range. Propagation delays are balanced (tPLH ≈ tPHL), and power dissipation remains low (ICC ≤ 80 μA typical @ 25°C).

Key Specifications

Pinout & Package

CD74HC73M is housed in a 14-pin Small Outline Integrated Circuit (SOIC) package with 8.65 mm × 3.90 mm body size, 1.27 mm lead pitch, and 1.75 mm max height - compatible with standard surface-mount reflow processes (MSL Level-1, 260°C peak).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual J-K flip-flop applications.

Compared with CD74HC73M, CD74HCT73M96.A trades supply flexibility for guaranteed TTL compatibility, while SN74HC73DR retains full HC functionality with updated packaging and lifecycle status - making it the recommended choice for new designs requiring long-term sourcing.

Availability

CD74HC73M is available at Aetrix Electronics and suitable for industrial PLC counter modules, automotive body control units, digital test equipment sequencers, and legacy system logic upgrades requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74HC73M 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 solutions, with over 90 years of innovation in high-reliability IC design and manufacturing.

The CD74HC73M belongs to TI's legacy HC logic family - engineered for low-power, high-noise-immunity digital control in harsh environments, targeting industrial automation, aerospace, and automotive subsystems.

FAQ

What is the supply voltage range supported by CD74HC73M?

CD74HC73M operates from 2 V to 6 V DC, with guaranteed performance across the full –55°C to +125°C temperature range. At 2 V, it supports up to 4 MHz clock frequency; at 6 V, maximum fMAX reaches 35 MHz with 50 pF load. This wide range allows direct integration into mixed-voltage systems without external regulators or level shifters.

Does CD74HC73M have hysteresis on its clock inputs?

Yes, CD74HC73M includes built-in hysteresis on both clock inputs (Pins 2 and 12), providing improved noise immunity and enabling reliable operation with slow-rising or noisy clock signals. This feature ensures stable triggering even when input rise/fall times reach 1000 ns at 2 V supply, reducing susceptibility to false edges in electrically noisy environments.

Can CD74HC73M replace 74LS73 in existing designs?

CD74HC73M can replace 74LS73 in most cases due to identical pinout, truth table, and negative-edge-triggered J-K functionality. However, note that CD74HC73M has higher input impedance and lower power consumption, so pull-up/down resistors may require adjustment. Also, verify that the 2–6 V supply range aligns with the target system's voltage rails.

What is the meaning of the "M" suffix in CD74HC73M?

The "M" in CD74HC73M denotes the SOIC (Small Outline Integrated Circuit) package type per TI's ordering nomenclature. Specifically, CD74HC73M corresponds to the obsolete SOIC-14 variant, while active versions use suffixes like "M96.A" - indicating tape-and-reel packaging (2500 pcs/reel), RoHS compliance, and MSL Level-1 reflow rating.

How does the asynchronous reset function in CD74HC73M?

CD74HC73M features two independent active-low asynchronous reset inputs: Pin 1 (1CLR̅) for the first flip-flop and Pin 13 (2CLR̅) for the second. When either is pulled LOW, the corresponding Q output immediately goes LOW and Q̅ goes HIGH - regardless of clock state or J/K inputs. This enables immediate, clock-independent initialization critical for safety-critical or startup-reset scenarios.