Texas Instruments SN74HC541N

Overview

SN74HC541N from Texas Instruments is an octal non-inverting 3-state buffer/line driver in PDIP-20 package, operating from 2 V to 6 V supply, delivering ±6 mA output drive at 5 V, with typical propagation delay of 10 ns (CL = 50 pF), and used for bus interfacing and LED driving in industrial control and embedded systems.

For engineers reviewing the SN74HC541N datasheet, SN74HC541N pinout, SN74HC541N application, or SN74HC541N equivalent, key selection criteria include its dual active-low output-enable architecture, data-flow-through pinout for PCB layout simplification, high-current 3-state outputs compatible with LSTTL loads, and wide-voltage CMOS logic compatibility across 2–6 V rails.

Technical Context

The SN74HC541N implements eight independent non-inverting buffers, each with true (non-inverted) input-to-output signal path. Its two-input NOR-based output-enable logic requires both OE1 and OE2 to be low for output activation; either high forces all Y outputs into high-impedance state.

Designed for bus-oriented applications, it features inputs on pins 1–9 and outputs on pins 11–18 - opposite-side pinout enabling straight trace routing. It meets standard HC logic thresholds (VIH = 3.15 V min at VCC = 4.5 V; VIL = 1.35 V max), supports up to 15 LSTTL loads, and exhibits low quiescent current (80 µA max ICC).

Key Specifications

Pinout & Package

SN74HC541N uses a 20-pin Plastic Dual In-line Package (PDIP) with 24.33 mm × 6.35 mm body size and through-hole mounting. Pin 1 is top-left corner with notch orientation marking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal 3-state buffer applications.

Compared with SN74HC541N, SN74HCT541N offers superior TTL input compatibility at the cost of higher static current, while 74AC541PC delivers significantly faster switching and stronger drive but with reduced noise immunity - making SN74HC541N optimal for general-purpose, low-power, mixed-voltage bus interfacing where robustness and simplicity are prioritized.

Availability

SN74HC541N is available at Aetrix Electronics and suitable for industrial control systems, embedded instrumentation, and legacy electronics repair requiring stable component supply and long-term obsolescence management.

Supply support for SN74HC541N 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 50 years of innovation in high-reliability logic families.

The SN74HC541N belongs to TI's HC (High-Speed CMOS) logic product line, designed for low-power, wide-voltage digital interfacing in industrial, automotive, and computing applications where noise immunity and compatibility across voltage domains are critical.

FAQ

What is the maximum output current per channel for SN74HC541N?

The SN74HC541N provides ±6 mA output drive capability per channel at VCC = 5 V, as specified in the Electrical Characteristics table (Section 6.7). This allows direct driving of LEDs or termination of bus lines without external amplification. Exceeding this current may cause VOL degradation or thermal stress, especially under sustained load conditions.

Does SN74HC541N support 3.3 V logic systems?

Yes, SN74HC541N operates across 2 V to 6 V, fully supporting 3.3 V logic systems. At VCC = 3.3 V, VIH is 2.31 V (70% of VCC) and VIL is 0.99 V (30% of VCC), ensuring reliable interfacing with standard 3.3 V CMOS outputs. Its 3-state outputs remain compatible with 3.3 V bus voltages without level-shifting.

How should unused inputs be handled on SN74HC541N?

All unused inputs on SN74HC541N - including A1–A8 and OE1/OE2 - must be tied to a valid logic level (VCC or GND) to prevent floating states that cause increased ICC, oscillation, or undefined output behavior. OE pins should be pulled up to VCC via a resistor (e.g., 10 kΩ) to ensure high-impedance default on power-up.

What is the typical propagation delay of SN74HC541N at 5 V supply?

At VCC = 5 V and CL = 50 pF, the typical propagation delay (tpd) of SN74HC541N is 12 ns (min 4.5 ns, max 23 ns), as listed in Section 6.10 of the datasheet. This value reflects the delay from A-input to corresponding Y-output under standard test conditions and is critical for timing budget allocation in synchronous bus designs.

Can SN74HC541N replace SN74LS244 in existing designs?

SN74HC541N can replace SN74LS244 in many cases due to identical pinout (PDIP-20), same 3-state functionality, and improved DC specs (lower ICC, higher noise margin). However, note that HC logic has different input thresholds and slower edge rates than LS - verify timing margins and bus loading in the target application before substitution.