The LM3525 is a single-port USB power switch and over-current protection from TI. It is compatible with USB1.1 and USB2.0 standards, and has a 1ms fault flag delay, which can prevent erroneous over-current reporting caused by inrush currents during hot-plug events. The device is packaged in SO-8, and has a small size and low RON, making it an ideal choice for root hubs and ganged power control in space-critical self-powered hubs.
The LM3525 provides a USB‑compliant high‑side power switch with built‑in over‑current, thermal shutdown and UVLO protection. It operates from 2.7 V to 5.5 V, delivers a typical continuous load current of 0.5 A and can tolerate a short‑circuit current of up to 1 A. A 1 ms fault‑flag delay prevents false fault reports during hot‑plug events.
Typical applications include USB root hubs for notebooks and desktop PCs, self‑powered hubs, and any high‑power USB device that requires in‑rush current limiting. The datasheet also gives PCB layout guidelines, component selection advice, and mechanical dimensions for the SO‑8 package.
| Input voltage range | 2.7 V – 5.5 V |
|---|---|
| Typical continuous output current | 0.5 A |
| Maximum short‑circuit output current | 1 A |
| On‑resistance (Ron) | 80 – 120 mΩ at 5 V |
| UVLO turn‑on threshold | 1.9 V |
| Fault flag delay | 1 ms |
The fault flag delay is 1 ms, which prevents erroneous fault reports during hot‑plug events.
The device can tolerate up to 1 A short‑circuit output current.
It operates from 2.7 V to 5.5 V.
The typical continuous load current is 0.5 A.