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STCC2540

Application information

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Application information

The STCC2540 device is designed to be implemented into the PC on a USB port in order to

emulate the wall charger adapter when the PC is in standby mode or OFF, and to allow

higher charge current when the USB interface is used for data communication. In order to

handle these functionalities, the STCC2540 device relies on USB BC1.2 specifications,

Chinese telecommunications industry standard YD/T 1591-2009, and proprietary

implementations.

•

BC1.2 charging profiles are

–

CDP: charging downstream port providing data communication plus charging

(active USB data communications with 1.5 A support)

–

SDP: standard downstream port providing data communication with no charging

(active USB 3.0 data communications with 900 mA support or USB 2.0 data

communications with 500 mA support)

–

DCP: dedicated charging port (wall charger emulation with no data communication

and 500 mA to 1.5 A support)

•

Chinese telecommunications standard

–

D+ and D- shorted to allow charging

•

Apple divider mode (2 A max. current)

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BlackBerry emulator mode

•

Legacy mode (allowing 500 mA charging current)

•

Korean tablet charging mode (D+ and D- shorted and pulled up to a certain voltage)

Figure 4. Typical application diagram