Texas Instruments CD74HC4049M

Overview

CD74HC4049M from Texas Instruments is a high-speed CMOS hex inverting buffer with level-shifting capability, designed for bidirectional logic-level translation between 15-V and 5-V domains. It features six independent inverting channels, operates from 2V to 6V VCC, supports –55°C to 125°C temperature range, and delivers 6ns typical propagation delay at 5V/15pF. It is used in industrial control interfaces where legacy high-voltage logic must drive modern low-voltage microcontrollers.

For engineers reviewing the CD74HC4049M datasheet, CD74HC4049M pinout, CD74HC4049M application, or CD74HC4049M equivalent, key selection criteria include its 16-V absolute input voltage rating, inverting-only topology, SOIC-16 package thermal profile (θJA = 73°C/W), LSTTL fanout compatibility, and absence of non-inverting functionality compared to the HC4050 family.

Technical Context

The CD74HC4049M implements a modified input protection structure enabling robust high-to-low voltage level translation-e.g., converting 15-V input pulses to 0–5-V CMOS-compatible outputs while powered solely from the 5-V rail. Its input stage tolerates –0.5V to +16V, exceeding standard CMOS input limits, and includes ESD protection against negative electrostatic discharge.

This device belongs to the HC logic family and is not TTL-compatible in input thresholds; it requires VIH ≥ 3.15V at VCC = 4.5V and VIL ≤ 1.35V. Unlike HCT variants, it does not guarantee 5-V TTL input compatibility, and its output drive strength is rated at ±25mA per pin with CMOS load characteristics.

Key Specifications

Pinout & Package

CD74HC4049M is housed in a 16-pin SOIC (Small Outline Integrated Circuit) package with standard 1.27mm pitch, JEDEC MS-012AC compliant, and moisture sensitivity level (MSL) Level-1 (unlimited floor life at <30°C/60% RH).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar inverting level translation applications.

Compared with CD74HC4049M, CD74HC4049M96G4 offers identical performance in a production-ready tape-and-reel format, while SN74LVTH16244DGGR serves a different architectural role-high-drive 3.3-V buffering without voltage translation-making it unsuitable for direct replacement in mixed-voltage interface designs.

Availability

CD74HC4049M is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and military data acquisition systems requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for CD74HC4049M 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 decades of heritage in high-reliability logic families including the 74HC series.

The CD74HC4049M belongs to TI's industry-standard 74HC logic portfolio, engineered specifically for robust mixed-voltage interfacing in harsh-environment applications such as factory automation, transportation, and defense systems.

FAQ

What is the maximum input voltage the CD74HC4049M can tolerate?

The CD74HC4049M supports an absolute maximum input voltage of +16V, verified per its Absolute Maximum Ratings table. This allows direct connection to 12-V or 15-V logic sources without external clamping diodes or resistive dividers. The device maintains functional integrity at this voltage when VCC is supplied within its 2V–6V range, and the input protection structure prevents damage from transient overvoltage events up to this limit. Always observe the –0.5V to +16V input range specified in the CD74HC4049M datasheet.

Is CD74HC4049M pin-compatible with CD74HC4050M?

No, CD74HC4049M and CD74HC4050M are not pin-compatible. Although both are 16-pin SOIC devices with identical pin counts and package outlines, their pin functions differ: CD74HC4049M is inverting (A→Y inversion), while CD74HC4050M is non-inverting (A→Y buffer). For example, pin 1 is 1A on CD74HC4049M but 1Y on CD74HC4050M. Substituting one for the other without board revision will invert logic states and likely cause system failure. Always verify pin mapping using the respective functional diagrams in the CD74HC4049M and CD74HC4050M datasheets.

Does CD74HC4049M support 3.3-V operation?

Yes, CD74HC4049M fully supports 3.3-V operation. Its HC-family specification guarantees functionality across 2V–6V VCC, including 3.3V nominal supplies. At VCC = 3.3V, VIH is guaranteed ≥ 2.1V and VIL ≤ 1.1V, ensuring reliable interfacing with standard 3.3-V CMOS outputs. Propagation delay increases slightly (to ~10ns at CL = 15pF), but remains well within timing budgets for most control logic. The CD74HC4049M maintains full –55°C to +125°C performance at 3.3V, making it suitable for low-power embedded applications.

Can CD74HC4049M be used as a non-inverting buffer?

No, CD74HC4049M cannot function as a non-inverting buffer. It contains six dedicated inverting buffers only; there is no internal configuration or external wiring that yields true non-inverting behavior. Cascading two CD74HC4049M stages per signal achieves net non-inversion but doubles propagation delay (~12ns), consumes two pins per signal, and increases power and noise susceptibility. For non-inverting applications, use CD74HC4050M instead-the complementary part in the same family, with identical package, temperature range, and voltage ratings but non-inverting logic.

What is the thermal resistance (θJA) of CD74HC4049M in SOIC package?

The junction-to-ambient thermal resistance (θJA) of CD74HC4049M in its SOIC (D) package is 73°C/W, as specified in the Thermal Information section of the datasheet. This value assumes standard JEDEC 2-layer board conditions (1-inch² copper pad, 2 oz Cu). Actual θJA in end equipment depends on PCB layout-adding thermal vias under the exposed pad (if present) or increasing copper area can reduce effective θJA by 15–25%. For continuous 25mA output current per pin at 125°C ambient, junction temperature remains below 150°C (max plastic package rating) only if power dissipation stays under ~350mW, requiring careful thermal design in high-density layouts.