USB3450 Datasheet, PDF (14/40 Pages) SMSC Corporation – HI-SPEED USB HOST OR DEVICE PHY WITH UTMI+INTERFACE

Hi-Speed USB Host or Device PHY With UTMI+ Interface
Table 3.1 USB3450 Pin Definitions (continued)
Datasheet
DIRECTION, ACTIVE
PIN
NAME
TYPE
LEVEL DESCRIPTION
36
XI
37
VDDA1.8
38
VDD3.3
39
VDD3.3
40
RBIAS
GND FLAG
Input,
Analog
N/A
N/A
N/A
Analog,
CMOS
Ground
N/A Crystal pin. A 24MHz crystal is supported. The
crystal is placed across XI and XO. An external
24MHz clock source may be driven into XI in place
of a crystal.
N/A 1.8V regulator output for analog circuitry on chip.
Place a 0.1uF capacitor near this pin and connect
the capacitor from this pin to ground. In parallel,
place a 4.7uF low ESR capacitor near this pin and
connect the capacitor from this pin to ground. See
Section 6.6.1, "Internal Regulators".
N/A 3.3V PHY Supply. Provides power for Hi-Speed
Transceiver, UTMI+ Digital, Digital I/O, and
Regulators.
N/A 3.3V PHY Supply. Should be connected directly to
pin 39.
N/A External 1% bias resistor. Requires a 12KΩ resistor
to ground.
N/A Ground. The flag must be connected to the ground
plane.
Revision 0.1 (05-11-05)
14
DATASHEET
SMSC USB3450