The SN65220 is a single transient voltage suppressor and the SN65240 and SN75240 are dual transient voltage suppressors designed to provide electrical noise transient protection to Universal Serial Bus (USB) full-speed ports. Note that the input capacitance of the device makes it unsuitable for high-speed USB 2.0 applications.

Any cabled I/O can be subjected to electrical noise transients from various sources. These noise transients can cause damage to the USB transceiver and/or the USB ASIC if they are of sufficient magnitude and duration.

USB ports are typically implemented in 3-V or 5-V digital CMOS with very limited ESD protection. The SN65220, SN65240, and SN75240 can significantly increase the port ESD protection level and reduce the risk of damage to the circuits of the USB port.