Texas Instruments CD74HC4049PW

Overview

CD74HC4049PW from Texas Instruments is a high-speed CMOS hex inverting buffer with level-shifting capability, designed for bidirectional logic-level translation between 15-V inputs and 2–6-V logic supplies. It features 6 independent inverting channels, 6ns typical propagation delay at 5V/15pF, –55°C to 125°C operating range, and input tolerance up to 16V - enabling use in industrial sensor interfacing and legacy system integration.

For engineers reviewing the CD74HC4049PW datasheet, CD74HC4049PW pinout, CD74HC4049PW application, or CD74HC4049PW equivalent, key selection criteria include its high-to-low voltage level conversion (up to 16V → 5V), TSSOP-16 package thermal performance (θ_JA = 108°C/W), LSTTL fanout compatibility (10 loads), and operation across full military temperature range.

Technical Context

The CD74HC4049PW implements silicon-gate CMOS technology with a modified input protection structure that enables robust high-voltage input handling (–0.5V to 16V) while operating from a low-voltage V_CC supply (2–6V). Its six independent inverting buffers support true level translation without external biasing.

Each channel delivers balanced t_PLH/t_PHL propagation delays (14–26ns over temperature/voltage) and fast transition times (13–22ns), with input capacitance of 10pF and power dissipation capacitance of 35pF at 5V - critical for timing-critical digital interface design.

Key Specifications

Pinout & Package

TSSOP-16 package (4.4mm × 5.0mm, 0.65mm pitch), thermally rated at θ_JA = 108°C/W - suitable for compact, high-density PCB layouts with moderate power dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CD74HC4049PW, CD74HC4049PWR offers identical functionality in tape-and-reel packaging for production lines, while SN74LVX4049PW trades 16V input capability for lower voltage operation and reduced delay - making it unsuitable for legacy voltage translation but viable in pure 3.3V domains.

Availability

CD74HC4049PW is available at Aetrix Electronics and suitable for industrial sensor interface, legacy system integration, military data acquisition, and automotive body control applications requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for CD74HC4049PW 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 high-reliability IC development.

The CD74HC4049PW belongs to TI's legacy HC logic family - engineered for robustness in harsh environments, emphasizing wide voltage operation, high noise immunity, and extended temperature performance for industrial and defense applications.

FAQ

What is the maximum input voltage rating for CD74HC4049PW?

The CD74HC4049PW supports an absolute maximum input voltage of –0.5V to 16V, as specified in the Absolute Maximum Ratings table. This allows direct interfacing with 12V and 15V logic sources without external attenuation. The device uses a modified input protection structure to sustain this range while operating from a 2–6V V_CC supply. Exceeding 16V risks permanent damage per TI's caution notice.

Is CD74HC4049PW pin-compatible with CD74HC4050PW?

No, CD74HC4049PW is not pin-compatible with CD74HC4050PW. While both are TSSOP-16 hex buffers, CD74HC4049PW provides inverting outputs (1Y = NOT 1A), whereas CD74HC4050PW provides non-inverting outputs (1Y = 1A). Their pinouts differ: CD74HC4049PW places GND at pin 7 and V_CC at pin 8, while CD74HC4050PW swaps these positions (GND at pin 8, V_CC at pin 16), making direct substitution impossible without PCB revision.

What is the thermal resistance (θ_JA) of CD74HC4049PW in its TSSOP package?

The CD74HC4049PW in TSSOP-16 package has a junction-to-ambient thermal resistance (θ_JA) of 108°C/W, as documented in the Thermal Information section. This value assumes standard JEDEC high-K board conditions (2S2P). Designers must account for this higher θ_JA versus SOIC (73°C/W) or PDIP (67°C/W) variants when estimating junction temperature rise under load - especially in compact, poorly ventilated enclosures.

Does CD74HC4049PW support operation at 3.3V V_CC?

Yes, CD74HC4049PW fully supports 3.3V V_CC operation within its specified 2V–6V range. At 3.3V, it delivers guaranteed VOH ≥ 3.15V and VOL ≤ 0.1V under 0.02mA load, with propagation delay increasing to ~21ns (max) at –40°C to 85°C. Input thresholds scale proportionally (VIH ≥ 2.31V, VIL ≤ 1.0V), ensuring reliable interfacing with standard 3.3V logic families.

Are pins 15 and 16 on CD74HC4049PW functional or no-connect?

Pins 15 and 16 on CD74HC4049PW are explicitly designated as NC (no-connect) in the TI datasheet and functional diagram. They are not internally bonded and must remain unconnected in the PCB layout. Routing traces to or placing vias on these pins violates TI's recommended usage and may compromise ESD performance or cause unpredictable behavior due to floating metal.