Diodes' power switch family protects USB port

Diodes Incorporated has extended its series of USB power switches with the introduction of 12 parts, providing a small form fit for USB ports in a wide range of consumer electronics. Offering designers 0.75A, 1.5A and 2.1A current limiting options and a choice of active-high and active-low enable, the AP21XX optimises port protection in a host of different systems. The AP21XX high-side power switch range has been created for USB port applications requiring fast response, high accuracy over-current and over-temperature protection, such as HD televisions, the set top boxes and PCs. Both single and dual channel power switches are available, with all devices being optimised for self-powered and bus-powered USB applications and fully compliant with all USB standards.



The power switches include an internal sensing field effect transistor which monitors for over-current conditions, without increasing series resistance in the current path, and an over-temperature sensor. If either over-current or over temperature conditions are sensed, the device switches into its current limiting mode. To prevent unwanted tripping when a high capacitive load is connected to the device output, a 7ms deglitch timeout has also been included in the AP21XX's design.



The USB power switch family is provided in small footprint SOT25, SOP-8L and MSOP-8L-EP packages. All of which are direct replacements for existing industry standard parts. Device operating ambient temperature range is -40 to 85oC.