USB3320C-EZK Standard Microsystems (SMSC), USB3320C-EZK Datasheet - Page 37

• Manufacturer Part Number: USB3320C-EZK
• Description: USB PHY
• Manufacturer: Standard Microsystems (SMSC)

Specifications of USB3320C-EZK

• Lead Free Status / RoHS Status: Compliant

Highly Integrated Full Featured Hi-Speed USB 2.0 ULPI Transceiver
Datasheet
SMSC USB3320
5.6.2.2
5.6.2.3
APPLICATION
Standard Host
OTG Device
Peripheral
TYPICAL
Standard
SessVld Comparator
The SessVld comparator is used when the transceiver is configured as both an A and B device. When
configured as an A device, the SessVld is used to detect Session Request protocol (SRP). When
configured as a B device, SessVld is used to detect the presence of VBUS. The SessVld interrupts
can be disabled by clearing this bit in both the
Falling
can be read in the
Table
Note: The OTG Supplement specifies a voltage range for A-Device Session Valid and B-Device
VbusVld Comparator
The final VBUS comparator is the VbusVld comparator. This comparator is only used when the
USB3320 is configured as an A-device. In the USB protocol the A-device supplies the VBUS voltage
and is responsible to ensure it remains within a specified voltage range. The VbusVld comparator can
be disabled by clearing this bit in both the
Falling
comparator trip points are detailed in
The internal VbusValid comparator is designed to ensure the VBUS voltage remains above 4.4V.
The USB3320 includes the external vbus valid indicator logic as detail in the ULPI Specification. The
external vbus valid indicator is tied to a logic one. The decoding of this logic is shown in
below. By default this logic is disabled.
Note 5.3
4.7.
INDICATOR
EXTERNAL
registers. When the interrupts are disabled, the SessVld comparator is not disabled and its state
registers. When disabled, bit 1 of the
Session Valid comparator. The USB3320 transceiver combines the two comparators into one
and uses the narrower threshold range.
VBUS
USE
A peripheral should not use VbusVld to begin operation. The peripheral should use
SessVld because the internal VbusVld threshold can be above the VBUS voltage required
for USB peripheral operation.
0
1
1
1
1
1
1
0
USB Interrupt Status
Table 5.6 External VBUS Indicator Logic
PASS THRU
INDICATOR
X
X
1
1
0
0
1
1
DATASHEET
Table
COMPLEMENT
INDICATOR
37
register. The SessVld comparator trip point is detailed in
4.7.
USB Interrupt Status
USB Interrupt Enable Rising
USB Interrupt Enable Rising
X
0
1
0
1
0
1
X
Internal VbusVld comparator (Default)
Fixed 1
Fixed 0
Internal VbusVld comparator.
Fixed 0
Fixed 1
Fixed 0
Internal VbusVld comparator. This
information should not be used by the
Link.
(Note
register will return a 0. The VbusVld
RXCMD VBUS VALID
ENCODING SOURCE
5.3)
and
and
USB Interrupt Enable
USB Interrupt Enable
Revision 1.0 (07-14-09)
Table 5.6