Texas Instruments SN75240PWR

Overview

SN75240PWR from Texas Instruments is a quadruple unidirectional transient voltage suppressor (TVS) designed for ESD protection of USB full-speed and low-speed ports. It features 6.5-V minimum breakdown voltage, 35-pF typical input capacitance, ≤1-µA leakage at 6 V, 15-kV HBM ESD rating, and operates from 0°C to 70°C. It protects D+ and D− data lines in USB transceivers against electrical noise transients.

For engineers reviewing the SN75240PWR datasheet, SN75240PWR pinout, SN75240PWR application, or SN75240PWR equivalent, key selection considerations include its 8-pin TSSOP package, unidirectional clamping behavior, suitability for 12-Mbps USB 1.1 systems, and compatibility with 3-V/5-V CMOS transceivers - not high-speed USB 2.0.

Technical Context

The SN75240PWR integrates four independent unidirectional TVS diodes in a single monolithic IC. Each channel clamps positive transients above 6.5 V using Zener-triggered transistor action and negative transients via forward-biased diode conduction. Its internal structure avoids external biasing and requires no power supply.

It operates exclusively in two functional modes: high-impedance standby (below 6.5 V) and low-impedance shunt (during ESD events). The device routes transient energy directly to local ground through dedicated GND pins, relying on PCB layout - especially low-inductance ground vias and proximity to connectors - to achieve rated 15-kV HBM performance.

Key Specifications

Pinout & Package

TSSOP-8 (PW) package: 3.00 mm × 4.40 mm body, 1.2-mm maximum height, lead pitch 0.65 mm, RoHS-compliant NiPdAu finish, MSL Level-1 (260°C reflow).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient suppression applications.

Compared with SN65240PWR, SN75240PWR trades extended temperature range for lower cost and qualification scope in commercial USB systems; versus TPD2E001DRSR, it delivers higher channel count and proven 15-kV HBM performance at the expense of slightly higher capacitance - making it the preferred choice for legacy USB 1.1 host/peripheral protection where layout and thermal constraints permit.

Availability

SN75240PWR is available at Aetrix Electronics and suitable for USB full-speed host ports, USB peripheral interfaces, and industrial data logger USB connectors requiring stable component supply and long-term production continuity.

Supply support for SN75240PWR 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 company headquartered in Dallas, Texas, specializing in analog, embedded processing, and connectivity technologies with over 90 years of innovation in power management and signal conditioning.

The SN75240PWR belongs to TI's USB port protection product line, engineered specifically to address ESD vulnerability in legacy USB 1.1 implementations while maintaining compatibility with 3-V/5-V CMOS transceivers and minimizing signal distortion.

FAQ

What is the primary function of the SN75240PWR in a USB system?

The SN75240PWR functions as a quadruple unidirectional transient voltage suppressor that protects USB full-speed and low-speed data lines (D+, D−, and two auxiliary lines) from ESD and electrical noise transients. It clamps voltages above 6.5 V to ground, preventing damage to downstream USB transceivers or ASICs. Its passive architecture requires no external power, and it operates within a 0°C to 70°C ambient range.

Can the SN75240PWR be used in USB 2.0 high-speed applications?

No, the SN75240PWR is not suitable for USB 2.0 high-speed (480 Mbps) applications due to its 35-pF typical input capacitance, which degrades signal integrity at high frequencies. The datasheet explicitly states it is intended for USB low-speed and full-speed (12 Mbps) ports only. For high-speed USB 2.0, lower-capacitance alternatives such as TPD2E001DRSR (12 pF) or USB-IF-certified high-speed TVS arrays are required.

How many ground connections does the SN75240PWR require, and why?

The SN75240PWR requires connection of all four GND pins (pins 1, 3, 5, and 7) to a solid ground plane. This multi-ground configuration minimizes parasitic inductance in the ESD current path, ensuring effective shunting of fast-rising transients (e.g., 15-kV HBM pulses). Failure to connect all GND pins degrades both clamping speed and peak current handling, compromising system-level ESD immunity.

What is the significance of the SN75240PWR's 0°C to 70°C operating temperature range?

The 0°C to 70°C operating range defines the ambient temperature envelope in which the SN75240PWR guarantees full electrical performance, including 6.5-V breakdown voltage, ≤1-µA leakage, and 15-kV HBM ESD protection. This commercial-grade specification distinguishes it from the SN65240PWR (–40°C to 85°C), making SN75240PWR appropriate for indoor consumer electronics but unsuitable for automotive or extended-temperature industrial deployments.

Does the SN75240PWR require any external components for basic operation?

No, the SN75240PWR is a fully passive device requiring no external resistors, capacitors, or bias supplies. Its operation relies solely on internal p-n junctions and Zener-triggered transistor action. However, proper PCB implementation - including short traces to the USB connector, direct vias to a ground plane for all GND pins, and avoidance of stubs - is essential to achieve rated ESD performance. Layout, not external components, determines functional reliability.