PRIXP425BB Intel, PRIXP425BB Datasheet - Page 39

• Manufacturer Part Number: PRIXP425BB
• Description: IC NETWRK PROCESSR 266MHZ 492BGA
• Manufacturer: Intel

Specifications of PRIXP425BB

• Processor Type: Network
• Features: XScale Core
• Speed: 266MHz
• Voltage: 1.3V
• Mounting Type: Surface Mount
• Package / Case: 492-BGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 869046

General Hardware Design Considerations—Intel
plane processors
3.7.2
Figure 12.
3.7.3
December 2007
Document Number: 252817-008US
IXP42X Product Line
and IXC1100 Control
Plane Processors
USB_DPOS
USB_DNEG
(D+)
(D-)
Intel
Driver
USB Interface
USB Interface
Design Notes
The integrated USB in the IXP42X product line and IXC1100 control plane processors is
an USB-device-only controller, and it can get its power from the bus or supplies its
power: bus or self-powered devices. To maintain the signal integrity and to minimize
end-user termination problems, the termination is required for the processors’ USB
design, based on what kind of driver is used, whether the transceiver operates in full-
speed (12 Mbps) or low-speed (1.5 Mbps), and if the port is upstream or downstream.
For more details, refer to the Universal Serial Bus Specification, Revision 1.1.
The USB device controller, client only, integrated in the IXP42X product line and
IXC1100 control plane processors, is compliant with the Universal Serial Bus
Specification, Revision 1.1, and uses USB_DPOS and USB_DNEG as a differential
output driver to drive the USB data signal onto the USB cable. If designers want to
implement the USB_DPOS and USB_DNEG lines as downstream lines, 15-kΩ, pull-down
resistors must be used on the USB_DPOS and USB_DNEG lines.
Note that:
®
• If a 1.5-kΩ, pull-up resistor is connected to USB_DPOS line, the USB port is
identified as full-speed (12 Mbps). (See
resistor is connected to USB_DNEG line, the USB port is identified as low-speed
(1.5 Mbps).
USB
Port
24-27 Ω
24-27 Ω
USB_3V3
Intel
22 pF
®
IXP42X Product Line of Network Processors and IXC1100 Control Plane Processor
1.5 kΩ
®
IXP42X product line and IXC1100 control
47 µF
FERRITE
USB_VDD
22 pF
22 pF
0.1 µF
FERRITE
Figure 12 on page
4.7 µF
FERRITE
22 pF
0.1 µF
200 mA
39) If a 1.5-kΩ, pull-up
Hardware Design Guidelines
1
3
2
4
VBUS
D+
D-
B2257-03
39