EC49021

USB Charger Enhance IC

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4I01N-Rev.F002

4. The EC49021 support most of the common protocols:

■ USB Battery Charging Specification, Revision 1.2(BC 1.2)

■ China Telecommunications Industry Standard YD/T 1591-2009

■ Specified Divider Mode

5. There are three types of charging ports defined to provide different current to the USB device.

■ Standard downstream port(SDP)

■ Charging downstream port(CDP)

■ Dedicated charging port(DCP)

The BC1.2 specification defines the charging USB port that provides power for the portable device.

6. Dedicated Charging Port (DCP) The DCP is a downstream port on the device which generally allows portable devices

with fast charge at their maximum rated current. A USB charger with DCP can be a wall adapter or vehicle power

adapter. The electrical characteristics in the data D+ and D- data lines can identify the charging mode.

7. Short the D+ line to the D- line

The USB BC1.2 Specification and the China Telecommunications Industry Standard YD/T 1501-2009 define the D+ and

D- should be shorted. This is shown as below

8. Divider Mode

There are some different charging schemes for the DCP mode. All of them have different voltage levels on the D+ line

and D- line. This is shown as below

The EC49021 can detect the D+ line and D- line voltages automatically and provide the correct signals on the D+ and D-

pins for the different USB portable device to fast charge.

IMPORTANT NOTICE

The products are not intended for use in life support appliances, devices, or systems. Use in such

applications are expressly prohibited.