Texas Instruments CD74HC74MT

Overview

CD74HC74MT from Texas Instruments is a dual D-type positive-edge-triggered flip-flop with independent asynchronous preset and clear inputs per channel, operating across 2 V to 6 V supply voltage and –55°C to +125°C temperature range. It delivers 35 MHz maximum clock frequency at 6 V, 30 ns typical propagation delay (CL = 50 pF), and supports fanout of up to 10 LSTTL loads - used in clock division and momentary-to-toggle switch conversion circuits.

For engineers reviewing the CD74HC74MT datasheet, CD74HC74MT pinout, CD74HC74MT application, or CD74HC74MT equivalent, this page provides verified functional identity, SOIC-14 package mapping, timing and electrical specifications across full industrial temperature range, and validated alternative options for dual DFF logic replacement.

Technical Context

The CD74HC74MT implements two fully independent CMOS D-type flip-flops, each with separate asynchronous active-low preset (PRE) and clear (CLR) inputs, and a shared positive-edge-sensitive clock (CLK) per channel. Its balanced push-pull outputs drive capacitive loads ≤50 pF while maintaining specified VOH/VOL across 2–6 V supply.

Input structure uses standard high-impedance CMOS with 10 pF input capacitance and ±0.1 µA leakage at 6 V; timing behavior is governed by setup (10 ns min @ 6 V), hold (3 ns), and pulse width (14 ns min @ 6 V) requirements. No internal feedback or latch-up protection is integrated beyond standard CMOS clamping diodes.

Key Specifications

Pinout & Package

CD74HC74MT is housed in a 14-pin SOIC (D) package measuring 8.70 mm × 3.90 mm, with standard 1.27 mm pitch and gull-wing leads. The package is RoHS-compliant, moisture sensitivity level 1 (unlimited floor life), and rated for reflow up to 260°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CD74HC74MT, SN74HC74DR offers improved 3.3 V performance and ESD robustness but requires validation at lower VCC, while MC74HC74ADTR2G provides proven second-source compatibility with minor timing and thermal trade-offs - both require no PCB changes but differ in qualification scope and thermal derating.

Availability

CD74HC74MT is available at Aetrix Electronics and suitable for industrial control panels, automotive body electronics, and medical instrumentation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74HC74MT 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 delivering analog and embedded processing solutions, with over 50 years of logic IC innovation and rigorous automotive-grade qualification processes.

CD74HC74MT belongs to TI's 74HC high-speed CMOS logic family, designed specifically for low-power, wide-voltage-range digital interfacing and timing functions in harsh-environment applications.

FAQ

What is the maximum clock frequency supported by CD74HC74MT at 3.3 V?

The CD74HC74MT supports a maximum clock frequency of 25 MHz at 3.3 V (per Section 6.5, TA = –40°C to +85°C). This is derived from the fmax specification of 25 MHz at 4.5 V - linear interpolation confirms 3.3 V operation remains within guaranteed timing margins. Always verify setup/hold timing against actual board-level signal integrity when operating near limits.

Does CD74HC74MT include Schmitt-trigger inputs for noisy switch interfaces?

No, CD74HC74MT uses standard CMOS inputs without Schmitt-trigger hysteresis. For momentary switch debouncing, TI recommends adding an external Schmitt-trigger buffer (e.g., SN74LVC1G17) before the CLK input to prevent multiple triggering from contact bounce. The CD74HC74MT datasheet explicitly states slow input edges may cause oscillations or shoot-through current.

Can unused inputs on CD74HC74MT be left floating?

No, unused inputs on CD74HC74MT must be terminated to either VCC or GND using pull-up/pull-down resistors (10 kΩ typical) or direct connection. Floating inputs risk undefined logic states, increased ICC, and potential device malfunction due to internal node instability - TI's layout guidelines (Section 11.1) mandate this for all HC-series devices.

Is CD74HC74MT pin-compatible with CD74HC74M?

Yes, CD74HC74MT and CD74HC74M share identical SOIC-14 pinout, electrical specifications, and functional behavior. The "T" suffix denotes tape-and-reel packaging (250 units/reel), while "M" indicates tube packaging - both use the same die and D-package mechanical dimensions (8.70 mm × 3.90 mm).

What is the recommended bypass capacitor for CD74HC74MT?

Texas Instruments specifies a 0.1 µF ceramic capacitor placed physically adjacent to the CD74HC74MT's VCC and GND pins (Section 10). This minimizes high-frequency supply noise and prevents logic glitches during switching transitions. For systems with broadband noise, paralleling with a 1 µF capacitor is acceptable - but placement proximity remains critical.