Datasheet

Application information STCC2540
12/33 DocID024711 Rev 5
5 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)
 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
1. C
VBUS
required by the USB specification.
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