Texas Instruments CD74HC541E

Overview

CD74HC541E from Texas Instruments is a non-inverting octal buffer and line driver with three-state outputs, designed for bus interface and data routing in digital systems. It operates from 2 V to 6 V, delivers 9 ns typical propagation delay at 5 V/15 pF, drives up to 15 LSTTL loads, and supports –55℃ to 125℃ industrial/military temperature range.

For engineers reviewing the CD74HC541E datasheet, CD74HC541E pinout, CD74HC541E application, or CD74HC541E equivalent, this page provides verified functional mode behavior, thermal metrics, bus-driving capability, three-state control logic, and PDIP-20 package-specific layout guidance.

Technical Context

The CD74HC541E implements dual independent output-enable controls (OE1 and OE2) - either high forces all eight outputs into high-impedance state; both low enable non-inverting data transfer from A0–A7 to Y0–Y7. Its HC logic family ensures CMOS-level input compatibility and rail-to-rail output swing.

It features buffered inputs, balanced tPLH/tPHL transition times, and low dynamic power dissipation (CPD = 48 pF), making it suitable for noise-sensitive bus environments where fanout, timing predictability, and wide supply tolerance are critical.

Key Specifications

Pinout & Package

CD74HC541E is supplied in a 20-pin plastic dual in-line package (PDIP-N), with 25.40 mm × 6.35 mm body size, through-hole mounting, and standard 2.54 mm pin pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal non-inverting buffer applications.

Compared with SN74HC244N and CD74HCT541E, the CD74HC541E uniquely combines dual-output-enable control, 2–6 V operation, and military-grade temperature range - making it optimal for reconfigurable bus architectures requiring robust voltage scalability and fail-safe disable behavior.

Availability

CD74HC541E is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, avionics data bus interface, military communication backplane, and test equipment digital pattern generation requiring stable component supply across extended temperature and long lifecycle programs.

Supply support for CD74HC541E 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 90 years of innovation in high-reliability logic, power management, and signal chain technologies.

The CD74HC541E belongs to TI's CD74HC high-speed CMOS logic family, engineered for robust bus interface, noise immunity, and wide-temperature operation in mission-critical industrial, aerospace, and defense systems.

FAQ

What is the function of OE1 and OE2 on the CD74HC541E?

The CD74HC541E uses two active-low output enable inputs, OE1 and OE2. If either is HIGH, all eight Y outputs enter high-impedance state. Both must be LOW to enable non-inverting data transfer from A0–A7 to Y0–Y7. This dual-enable architecture allows flexible bus segmentation and fault-isolation control not found in single-OE buffers like the SN74HC244N. The CD74HC541E truth table confirms this OR-gated disable behavior.

Does the CD74HC541E support 3.3 V operation?

Yes, the CD74HC541E fully supports 3.3 V operation within its specified 2 V to 6 V supply range. At VCC = 3.3 V, it maintains valid VIH/VIL thresholds (≥2.0 V / ≤1.0 V), delivers rail-to-rail CMOS-compatible outputs, and achieves ~13 ns typical propagation delay (per interpolation from datasheet curves). This makes the CD74HC541E suitable for mixed-voltage systems interfacing 3.3 V FPGAs or microcontrollers with 5 V peripherals.

How does the CD74HC541E differ from the CD74HCT541E?

The CD74HC541E uses CMOS-compatible input thresholds (VIH = 70% VCC, VIL = 30% VCC), while the CD74HCT541E features TTL-compatible inputs (VIH = 2.0 V min, VIL = 0.8 V max) for direct connection to legacy 5 V TTL logic. Both share identical pinout, three-state behavior, and drive capability. The CD74HC541E offers broader supply flexibility (2–6 V); the CD74HCT541E is optimized for strict 4.5–5.5 V TTL system integration.

What thermal considerations apply to the CD74HC541E in PDIP package?

The CD74HC541E in PDIP (N) package has a junction-to-ambient thermal resistance (RθJA) of 84.6°C/W. At maximum rated ICC (160 μA) and worst-case output loading, self-heating remains negligible. However, under sustained 6 mA per output switching, power dissipation may reach ~30 mW - requiring no heatsink but advising adequate PCB copper area and airflow in sealed enclosures above 85℃ ambient. Derating guidelines per TI SCHS189E confirm safe operation up to 125℃ junction temperature.

Can unused inputs on the CD74HC541E be left floating?

No. All unused inputs on the CD74HC541E must be tied to a defined logic level - either VCC or GND - to prevent floating nodes that cause increased ICC, erratic output behavior, or ESD susceptibility. TI's layout guidelines explicitly require termination of unused A0–A7 and OE pins. Leaving them unconnected violates recommended practice and risks undefined functional states, especially under temperature extremes where input leakage may bias gates unpredictably. The CD74HC541E datasheet mandates this in Section 9.1.