Texas Instruments LM3526M-L

Overview

LM3526M-L from Texas Instruments is a dual-channel high-side USB power switch with active-low enable inputs, designed for per-port power control in USB 1.1/2.0 host applications. It delivers 500 mA continuous output current per channel, features 140 mΩ max on-resistance at 5 V, and integrates over-current protection with 1 ms fault flag delay to suppress hot-plug transients. Used in notebook/desktop PC root hubs and self-powered USB monitor hubs.

For engineers reviewing the LM3526M-L datasheet, LM3526M-L pinout, LM3526M-L application, or LM3526M-L equivalent, key selection criteria include its SOIC-8 package, active-low EN logic thresholds (≤0.8 V ON, ≥2.4 V OFF), thermal shutdown with dual-stage protection (145°C per switch, 150°C global), UVLO at 1.8 V, and 2.7–5.5 V input voltage range.

Technical Context

The LM3526M-L implements two independent P-channel MOSFET high-side switches with integrated current-limit sensing, thermal shutdown circuitry, and open-drain fault flag outputs. Each switch has dedicated enable (ENA/ENB) and flag (FLAG A/B) pins, enabling per-port control and diagnostics without shared failure propagation.

Its 1 ms over-current flag delay filters in-rush currents during USB hot-plug events, while the dual-stage thermal protection allows one switch to remain operational during localized overload-critical for maintaining port availability in multi-port hubs.

Key Specifications

Pinout & Package

LM3526M-L is housed in an 8-pin SOIC (D) package with 1.27 mm pitch, 3.91 mm width, and 4.9 mm length per TI package drawing D0008A. Pin 1 is marked by a beveled corner or dot; device orientation follows JEDEC MS-012 AA standard.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB power switch applications.

Compared with TUSB2036IPW and TPS2051BDBVR, the LM3526M-L uniquely delivers dual independent high-side switches with per-port thermal shutdown and active-low enable logic in a single SOIC-8 package-enabling compact, fault-resilient USB power architecture without protocol overhead or component duplication.

Availability

LM3526M-L is available at Aetrix Electronics and suitable for USB root hubs, self-powered monitor hubs, and industrial high-side switching applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for LM3526M-L 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 connectivity technologies, with decades of expertise in power management and interface ICs.

The LM3526 product line was engineered specifically for USB host port power control-delivering integrated over-current protection, thermal resilience, and logic-compatible enable interfaces for desktop, notebook, and embedded hub designs.

FAQ

What is the enable logic polarity of the LM3526M-L?

The LM3526M-L uses active-low enable inputs: ENA and ENB must be pulled to ≤0.8 V to turn on the respective switch, and held ≥2.4 V to disable it. This matches standard 3.3 V/5 V logic low-active signaling and distinguishes it from the LM3526M-H variant, which uses active-high enables. The LM3526M-L datasheet specifies these thresholds across −40°C to 85°C ambient temperature.

Does the LM3526M-L support USB 2.0 compliance?

Yes, the LM3526M-L is explicitly designed and specified for USB 1.1 and USB 2.0 host port applications. Its 500 mA continuous output current per channel, 140 mΩ max RON, and 1 ms fault flag delay meet USB 2.0 electrical requirements for downstream port power switching and in-rush current management. TI's official documentation confirms compatibility in both root and self-powered hub configurations.

How does thermal protection work in the LM3526M-L?

The LM3526M-L employs dual-stage thermal shutdown: if die temperature reaches ~145°C at a single switch, only that channel turns off while the other remains operational; if temperature exceeds 150°C globally, both switches disable and both FLAG outputs activate. Hysteresis resets operation at 135°C. This behavior is confirmed in the LM3526M-L datasheet's DC Electrical Characteristics and Functional Description sections.

What is the maximum output current limit of the LM3526M-L?

The LM3526M-L provides a short-circuit output current limit of 1.0 A typical per channel (min 0.5 A, max 1.9 A depending on VOUT), with a guaranteed minimum continuous output current of 500 mA. This limit protects the host power supply, the switch itself, and connected peripherals during overload conditions-and is internally set, requiring no external components.

Can the LM3526M-L be used outside USB applications?

Yes-the LM3526M-L functions as a general-purpose dual high-side switch with 2.7–5.5 V input, 500 mA continuous per channel, thermal/over-current/UVLO protection, and open-drain fault flags. Its SOIC-8 footprint and logic-compatible enables make it suitable for industrial control, battery-powered systems, and any application needing robust, independently monitored 5 V or 3.3 V load switching-beyond strict USB use cases.