Texas Instruments SN74HCT541NG4

Overview

SN74HCT541NG4 from Texas Instruments is an octal buffer and line driver IC with 3-state outputs, designed for bus interface and load-driving applications in 5-V TTL-compatible digital systems. It operates from 4.5 V to 5.5 V, delivers ±6 mA output drive at 5 V, exhibits typical propagation delay of 12 ns, and supports up to 15 LSTTL loads per output.

For engineers reviewing the SN74HCT541NG4 datasheet, SN74HCT541NG4 pinout, SN74HCT541NG4 application, or SN74HCT541NG4 equivalent, key selection criteria include its dual 3-state enable (OE1/OE2) architecture, data-flow-through pinout for PCB layout optimization, low 80-µA max ICC quiescent current, and TTL-voltage-compatible inputs enabling direct interfacing with legacy logic families.

Technical Context

The SN74HCT541NG4 implements eight independent non-inverting buffers, each with high-current 3-state outputs controlled by a dual-input NOR gate (OE1 and OE2). When either enable input is high, all outputs enter high-impedance state-ensuring clean bus isolation during contention or power-down sequences.

Its input structure is TTL-voltage compatible (VIH = 2 V min, VIL = 0.8 V max), while output voltage levels meet HCT logic thresholds (VOH ≥ 3.7 V at IOH = −6 mA, VOL ≤ 0.33 V at IOL = 6 mA), guaranteeing interoperability with both 5-V CMOS and bipolar TTL systems without level-shifting.

Key Specifications

Pinout & Package

SN74HCT541NG4 is supplied in a 20-pin PDIP (Plastic Dual In-line Package) with nominal body size 25.40 mm × 6.35 mm, through-hole mounting, and industry-standard 0.3-inch width. Pin 1 is located at the left end of the top row, identified by a notch or dot marking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal buffer and line driver applications.

Compared with SN74HCT541NG4, SN74HCT240N provides inverted logic and grouped enables-ideal for bidirectional bus control-while SN74ACT541N trades higher power for significantly faster switching and stronger drive, making it appropriate for demanding high-frequency interfaces where thermal management is feasible.

Availability

SN74HCT541NG4 is available at Aetrix Electronics and suitable for industrial control backplanes, legacy system bus interfaces, test equipment signal routing, and embedded data acquisition front-ends requiring stable component supply and long-term manufacturability.

Supply support for SN74HCT541NG4 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, embedded processing, and connectivity solutions for industrial, automotive, and consumer applications.

The SN74HCT541NG4 belongs to TI's 74HCT logic family, engineered for TTL-compatible operation in 5-V systems where low power, noise immunity, and bus-interface reliability are critical design priorities.

FAQ

What is the operating voltage range for SN74HCT541NG4?

The SN74HCT541NG4 operates over a supply voltage range of 4.5 V to 5.5 V. This 5-V nominal range ensures compatibility with standard TTL and CMOS logic families while accommodating typical industrial rail tolerances. Operation outside this range may cause functional failure or permanent damage, as specified in the absolute maximum ratings table of the official datasheet.

Does SN74HCT541NG4 support true or inverted output logic?

SN74HCT541NG4 provides true (non-inverting) output logic: each Yn output replicates the logic state of its corresponding An input when enabled. This distinguishes it from inverting variants like SN74HCT240N. The device's truth table confirms Y = A when OE1 and OE2 are both low, making SN74HCT541NG4 ideal for unidirectional signal buffering without polarity reversal.

How many LSTTL loads can SN74HCT541NG4 drive per output?

Each output of SN74HCT541NG4 can drive up to 15 LSTTL loads, enabled by its ±6-mA output drive capability at 5 V. This specification is explicitly stated in the device features and verified under recommended operating conditions. Driving more than 15 LSTTL loads risks exceeding output current limits and degrading VOH/VOL margins, potentially causing logic errors in downstream circuits.

What is the function of OE1 and OE2 pins on SN74HCT541NG4?

OE1 and OE2 are active-low 3-state enable inputs whose logic is combined via an internal NOR gate. If either OE1 or OE2 is high, all eight outputs (Y1–Y8) enter high-impedance state-effectively disconnecting them from the bus. Only when both OE1 and OE2 are low do the outputs actively drive their respective inputs. This dual-enable architecture enhances system-level fault tolerance and bus arbitration flexibility in SN74HCT541NG4 designs.

Is SN74HCT541NG4 pin-compatible with other 74HCT-series octal buffers?

SN74HCT541NG4 shares the same 20-pin PDIP footprint and pinout as SN74HCT240N and SN74HCT244N, but functional differences exist: SN74HCT240N offers inverting outputs and grouped enables, while SN74HCT244N has single-enable control. Therefore, SN74HCT541NG4 is mechanically pin-compatible but not functionally interchangeable without verifying logic polarity and enable behavior in the target application.