Usb (Universal Serial Bus); How The Usb Interface Works - Nokia 3155i Troubleshooting Manual

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USB (Universal Serial Bus)

How the USB Interface Works

When the mobile terminal is connected to a computer using a DKU-2 data cable, the
computer will provide Vbus (5V) to and pull down D+ a,d D – lines. The mobile terminal
will respond by pulling the D+ line high. The computer acknowledges and starts
transferring data at 12Mbits/sec.
©2005 Nokia Corporation
ISSUE 1 07/2005
Baseband Description and Troubleshooting
Figure 14: USB interface block diagram
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