Texas Instruments CD74HC4049E

Overview

CD74HC4049E 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 6 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 I/O interfacing where legacy high-voltage logic must drive modern low-voltage microcontrollers.

For engineers reviewing the CD74HC4049E datasheet, CD74HC4049E pinout, CD74HC4049E application, or CD74HC4049E equivalent, key selection criteria include its 16-V absolute input voltage rating, inverting-only topology, PDIP-16 package compatibility, and verified operation as a high-to-low voltage level converter without external biasing.

Technical Context

The CD74HC4049E implements six independent CMOS inverting buffers with modified input protection diodes enabling safe 0–15V input signal handling while powered from a 2–6V VCC rail. Its input structure clamps negative ESD transients and tolerates overvoltage beyond VCC without latch-up.

This device belongs to the HC logic family and exhibits balanced tPLH/tPHL propagation delays and transition times, ensuring minimal duty-cycle distortion in clock or data buffering applications. It draws ≤40µA quiescent current across the full temperature range and supports fanout of 10 LSTTL loads.

Key Specifications

Pinout & Package

CD74HC4049E is supplied in a 16-pin plastic dual in-line package (PDIP) with 0.3-inch body width and through-hole mounting. Pin 1 is located at the top-left corner adjacent to the notch or dot marking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar hex inverting buffer applications.

Compared with SN74LVX4049N and CD74HC4050E, the CD74HC4049E uniquely supports 15-V input translation while maintaining inverting logic - making it irreplaceable in legacy-to-modern voltage domain bridging where polarity must be preserved.

Availability

CD74HC4049E is available at Aetrix Electronics and suitable for industrial sensor interface, automotive body control, and legacy system integration requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74HC4049E 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 components.

The CD74HC4049E belongs to TI's industry-standard HC logic family, engineered for robust voltage translation and interoperability across mixed-voltage digital systems in harsh environments.

FAQ

What is the maximum input voltage rating for CD74HC4049E?

The CD74HC4049E supports an absolute maximum input voltage of 16V, allowing direct connection to 12-V or 15-V industrial signals without external attenuation. This rating is specified in the Absolute Maximum Ratings table and validated across the full –55°C to 125°C operating range. The CD74HC4049E achieves this via a modified input protection structure that safely clamps overvoltage transients while preventing latch-up.

Can CD74HC4049E operate with a 3.3-V supply?

Yes, CD74HC4049E operates fully across 2V to 6V VCC, including 3.3V nominal supplies. At 3.3V, it maintains guaranteed logic thresholds (VIH ≥ 2.31V, VIL ≤ 0.99V), 16V input tolerance, and ≤22ns propagation delay. Its HC-family design ensures compatibility with both 3.3V and 5V systems, making CD74HC4049E ideal for mixed-voltage board designs where legacy and modern logic coexist.

Is CD74HC4049E pin-compatible with CD74HC4050E?

Yes, CD74HC4049E and CD74HC4050E share identical PDIP-16 pinouts, electrical ratings, and package dimensions - differing only in logic function (inverting vs. non-inverting). This allows direct PCB substitution when signal polarity requirements change, with no layout modification needed. Both devices support the same 2–6V VCC range and 16V input tolerance, confirming functional interchangeability in non-inverting contexts.

Does CD74HC4049E require external pull-up resistors on inputs?

No, CD74HC4049E does not require external pull-up resistors on inputs. Its CMOS inputs have negligible leakage (≤±1µA), and the internal modified protection structure provides defined logic thresholds without external biasing. When driven by open-collector or high-impedance sources, however, a pull-up or pull-down may still be needed for deterministic state - but this is independent of CD74HC4049E's internal design.

What is the thermal resistance (θJA) of the CD74HC4049E PDIP package?

The CD74HC4049E in the PDIP (N) package has a junction-to-ambient thermal resistance (θJA) of 67°C/W, as specified in the Thermal Information section of the datasheet. This value assumes standard JEDEC 2-layer board conditions and enables thermal design margin calculation for continuous operation at up to 125°C ambient when power dissipation remains below ~150mW - well within typical logic-level translation use cases.