Texas Instruments SN74HC541PWR

Overview

SN74HC541PWR from Texas Instruments is an octal non-inverting 3-state buffer/line driver IC used for bus interfacing and signal isolation in digital logic systems. It operates from 2 V to 6 V, delivers ±6 mA output drive at 5 V, exhibits typical propagation delay of 10 ns (VCC = 6 V, CL = 50 pF), and supports high-current bus driving up to 15 LSTTL loads - commonly deployed in PC motherboard I/O expansion and industrial control backplanes.

For engineers reviewing the SN74HC541PWR datasheet, SN74HC541PWR pinout, SN74HC541PWR application, or SN74HC541PWR equivalent, key selection criteria include its dual active-low output-enable architecture (OE1/OE2), data-flow-through pinout for PCB layout simplification, 3-state output compatibility with shared bus topologies, and TSSOP-20 package suitability for space-constrained embedded designs.

Technical Context

The SN74HC541PWR implements eight independent non-inverting buffers, each with true (non-inverted) input-to-output mapping. Its 3-state outputs are controlled by a two-input NOR gate: both OE1 and OE2 must be low to enable outputs; either high forces all Y1–Y8 into high-impedance state.

This architecture enables bidirectional bus control without external logic. The device uses silicon-gate CMOS technology, ensuring low static current (80 µA max ICC), high noise immunity, and compatibility with TTL and CMOS logic families across its full 2–6 V supply range.

Key Specifications

Pinout & Package

TSSOP-20 package (6.50 mm × 4.40 mm body size, 0.65 mm pitch), thermally enhanced for surface-mount reflow assembly; pin 1 marked by dimple or notch orientation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC541PWR, SN74HCT541PW offers improved input compatibility with older TTL systems, while 74LVC541APW delivers superior speed and density at lower voltages - neither is pin-compatible for 5 V operation, making SN74HC541PWR the only choice for universal 2–6 V bus interfacing with guaranteed 5 V tolerance.

Availability

SN74HC541PWR is available at Aetrix Electronics and suitable for PC motherboard I/O expansion, industrial PLC backplane interface, and LED status indication subsystems requiring stable component supply across extended production lifecycles.

Supply support for SN74HC541PWR 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 industrial, automotive, and communications markets.

The SN74HC541PWR belongs to TI's HC logic family - designed for robust, low-power, wide-supply-range digital interfacing in cost-sensitive industrial and computing applications where reliability and long-term availability are critical.

FAQ

What is the function of OE1 and OE2 on the SN74HC541PWR?

The SN74HC541PWR features two active-low output-enable inputs (OE1 and OE2) that control all eight 3-state outputs. Both OE1 and OE2 must be driven low to enable data flow from A1–A8 to Y1–Y8; if either is high, all outputs enter high-impedance state. This dual-enable architecture supports fail-safe bus control and hierarchical enable schemes in complex digital systems - a core design feature of the SN74HC541PWR.

Can SN74HC541PWR operate at 3.3 V supply voltage?

Yes, SN74HC541PWR is fully specified for operation from 2 V to 6 V, including 3.3 V nominal systems. At VCC = 3.3 V, it delivers ±4 mA output drive (per datasheet Table 6.7), maintains VIH ≥ 2.31 V and VIL ≤ 0.99 V, and achieves typical tpd ≈ 15 ns (CL = 50 pF). This makes SN74HC541PWR suitable for mixed-voltage interfaces between 3.3 V MCUs and 5 V peripherals - a key capability of the SN74HC541PWR.

Is SN74HC541PWR pin-compatible with SN74HC244PWR?

No, SN74HC541PWR is not pin-compatible with SN74HC244PWR. While both are octal 3-state buffers in TSSOP-20 packages, their pinouts differ: SN74HC541PWR places OE1/OE2 on pins 1/19 and groups A1–A8 on pins 2–9, whereas SN74HC244PWR uses pins 1/19 for OE1/OE2 but assigns A1–A4 to pins 2–5 and A5–A8 to pins 12–15. This difference prevents direct substitution without PCB revision - a critical distinction for SN74HC541PWR users.

What is the maximum capacitive load SN74HC541PWR can drive reliably?

SN74HC541PWR is characterized for CL = 50 pF and CL = 150 pF loads. At VCC = 6 V, tpd increases from 10 ns (50 pF) to 14 ns (150 pF); transition time tt rises from 6 ns to 13 ns. For stable operation, TI recommends limiting total load capacitance (including trace and input capacitance) to ≤150 pF. Exceeding this may cause timing violations or increased power dissipation - verified in SN74HC541PWR switching characteristics tables (Sections 6.10 and 6.13).

Does SN74HC541PWR include bus-hold or weak pull-up circuitry on inputs?

No, SN74HC541PWR does not integrate bus-hold or weak pull-up circuitry. All inputs (A1–A8, OE1, OE2) must be actively driven or externally biased to a defined logic level (VCC or GND) to prevent floating states that could cause excessive ICC, logic glitches, or latch-up. This requirement is explicitly stated in Section 6.3 of the datasheet - a mandatory design consideration for reliable SN74HC541PWR implementation.