Texas Instruments 74ACT7541QWRKSRQ1

Overview

74ACT7541QWRKSRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive octal buffer with open-drain outputs, operating from 4.5V to 5.5V, delivering up to 75mA short-burst output drive at 5V, and featuring 9.6ns max propagation delay (VCC = 5V, CL = 50pF) for driving 50Ω transmission lines in body control modules.

For engineers reviewing the 74ACT7541QWRKSRQ1 datasheet, 74ACT7541QWRKSRQ1 pinout, 74ACT7541QWRKSRQ1 application, or 74ACT7541QWRKSRQ1 equivalent, key selection criteria include open-drain output configuration, dual active-low output enable (OE1/OE2), wettable-flank VQFN-20 package compatibility with AOI inspection, and automotive-grade thermal performance across –40°C to +125°C.

Technical Context

This device implements eight independent CMOS buffers with true open-drain outputs-each output actively pulls low or enters high-impedance state, never sourcing current. Dual active-low output enables (OE1 and OE2) require both to be asserted low for output activation, enabling robust shared control logic in fault-tolerant automotive subsystems.

Its TTL-compatible inputs accept standard 0.8V/2.0V thresholds under 4.5–5.5V supply, while output drive capability supports 24mA continuous or 75mA pulsed sink current into loads such as LEDs, relays, or wired-AND bus structures-enabling level-shifting and indicator control without external pull-ups on the driver side.

Key Specifications

Pinout & Package

VQFN-20 (RKS) package with wettable flanks, 4.5mm × 2.5mm body size, exposed thermal pad (connectable to GND or left floating), optimized for automated optical inspection and thermal dissipation in space-constrained automotive modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal open-drain buffer applications.

Compared with SN74ACT7541QPWRQ1 and SN74ACT7541QDGSRQ1, the 74ACT7541QWRKSRQ1 delivers superior thermal performance (67.7°C/W) and manufacturability assurance via wettable flanks - critical for zero-defect automotive production targeting engine compartment or power distribution modules.

Availability

74ACT7541QWRKSRQ1 is available at Aetrix Electronics and suitable for automotive body control modules, LED lighting systems, relay interface circuits, and wired-AND fault-bus implementations requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for 74ACT7541QWRKSRQ1 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 automotive-grade logic solutions with over 50 years of automotive qualification experience.

The SN74ACT7541-Q1 belongs to TI's automotive-qualified ACT logic family, designed specifically for robust signal buffering and level translation in harsh-temperature vehicle subsystems including body electronics, lighting, and power distribution.

FAQ

What is the maximum continuous output current rating for the 74ACT7541QWRKSRQ1?

The 74ACT7541QWRKSRQ1 supports 24mA continuous output sink current per channel at 5V supply, as specified in the Recommended Operating Conditions table. This rating ensures stable operation without thermal derating in sustained LED or sensor interface applications. Exceeding this value continuously risks exceeding junction temperature limits - the device also supports up to 75mA in short bursts, but only with appropriate duty cycle and thermal design.

Does the 74ACT7541QWRKSRQ1 require external pull-up resistors on its outputs?

Yes, the 74ACT7541QWRKSRQ1 requires external pull-up resistors on all Y1–Y8 outputs because it features open-drain outputs that can only sink current. A typical value is 10kΩ to 5V, selected to balance rise time, power consumption, and noise immunity. The resistor value must be chosen based on load capacitance and desired edge rate - for example, with >50pF capacitive load, a series resistor may be needed to prevent overshoot.

How are the output enable pins OE1 and OE2 configured in the 74ACT7541QWRKSRQ1?

In the 74ACT7541QWRKSRQ1, both OE1 and OE2 are active-low inputs that share control logic: outputs Y1–Y8 become active (driving low or high-impedance based on A1–A8 inputs) only when both OE1 and OE2 are low. If either is high, all outputs enter high-impedance state. This dual-enable architecture enhances functional safety by requiring two independent control signals to activate outputs - reducing risk of unintended actuation in automotive systems.

Is the thermal pad on the 74ACT7541QWRKSRQ1 package required to be connected to ground?

No, the thermal pad on the 74ACT7541QWRKSRQ1 (RKS VQFN) can be connected to GND or left electrically floating - TI's datasheet explicitly states "Do not connect to any other signal or supply." Connecting to GND improves thermal conduction and EMI performance, but floating is acceptable if PCB layout constraints or grounding schemes prohibit it. Regardless of connection, the pad must be soldered to the PCB for mechanical stability and thermal transfer.

Can the 74ACT7541QWRKSRQ1 interface directly with 3.3V microcontrollers?

Yes, the 74ACT7541QWRKSRQ1 accepts 3.3V logic-high inputs reliably due to its TTL-compatible input structure with VIH(min) = 2.0V at 4.5–5.5V supply - well below typical 3.3V MCU VOH levels (~3.0V). Its inputs are high-impedance CMOS with ≤1µA leakage, minimizing loading. However, outputs remain 5V-referenced, so external pull-up to 5V is required to achieve full HIGH-level voltage - making it ideal for 3.3V-to-5V level shifting in automotive gateway applications.