Connectivity designer Pericom Semiconductor has announced a new USB switch that will allow USB devices such as an iPhone to charge, while the operating system remains in sleep mode.

Dubbed the Pericom PowerNap switch, it essentially allows the user to connect his or her USB device to a laptop or desktop in order for it to charge, but without the operating system waking up.

Previously the OS would need to be running in order for a charge to go through the USB connection, which could be a problem for a laptop not plugged into for example, as it would drain the battery.

Pericom says that its PI5USB56 all-in-one USB PowerNap controller is the first of the PI5USB5X series with auto-detection and auto-switching support for mobile device charging, which it is dubbing "sleep-and-charge" functionality. It fully supports USB1.1, USB2.0 full speed and high-speed specifications.

With the PI5USB56 IC, system designers therefore don't need to consider any software intervention requirements. This is because the integrated circuit supports automatic detection and switching.

"Major OEMs are already implementing PowerNap solutions to support the sleep-and-charge features in their products," said Abdullah Raouf, product manager of USB Switch Solutions, in a statement.

Raouf cited Gartner figures that 150 million mobile PCs will be shipped in 2010, with approximately 10 percent of this volume containing some type of added mobile device charging capability.

"Our unique new charger IC can address most of these sockets and also offer the designer much value add to his notebook design with our PowerNap technology," said Raouf.

The PI5USB56 will enter production at the end of the year, but samples are available now.

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