USB3500-ABZJ Standard Microsystems (SMSC), USB3500-ABZJ Datasheet - Page 41

• Manufacturer Part Number: USB3500-ABZJ
• Manufacturer: Standard Microsystems (SMSC)

Specifications of USB3500-ABZJ

• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Operating Temperature (max): 70C
• Package Type: QFN
• Rad Hardened: No
• Lead Free Status / Rohs Status: Compliant

Hi-Speed USB Host, Device or OTG PHY With UTMI+ Interface
Datasheet
SMSC USB3500
7.12
7.13
PARAMETER
TIMING
T0
T1
T2
T3
T4
Detection of Resume
HS Device Attach
Resume signaling always takes place in FS mode (TERMSELECT and XCVRSELECT = FS enabled),
so the behavior for a HS device is identical to that of a FS device. The Link uses the LINESTATE
signals to determine when the USB transitions from the 'J' to the 'K' state and finally to the terminating
FS EOP (SE0 for 1.25us-1.5µs.).
The resume signaling (FS 'K') will be asserted for at least 20ms. At the beginning of this period the
Link may negate SUSPENDN, allowing the transceiver (and its oscillator) to power up and stabilize.
The FS EOP condition is relatively short. Links that simply look for an SE0 condition to exit suspend
mode do not necessarily give the transceiver’s clock generator enough time to stabilize. It is
recommended that all Link implementations key off the 'J' to 'K' transition for exiting suspend mode
(SUSPENDN = 1). And within 1.25µs after the transition to the SE0 state (low-speed EOP), the Link
must enable normal operation, i.e. enter HS or FS mode depending on the mode the device was in
when it was suspended.
If the device was in FS mode: then the Link leaves the FS terminations enabled. After the SE0 expires,
the downstream port will assert a J state for one low-speed bit time, and the bus will enter a FS Idle
state (maintained by the FS terminations).
If the device was in HS mode: then the Link must switch to the FS terminations before the SE0 expires
(< 1.25µs). After the SE0 expires, the bus will then enter a HS IDLE state (maintained by the HS
terminations).
Figure 7.8
a HS device is attached to an upstream port, power is asserted to the device and the device sets
XCVRSELECT and TERMSELECT to FS mode (time T1).
V
within normal operational range as defined in the USB 2.0 specification. The assertion of Device Reset
(T0) by the upstream port will initialize the device. By monitoring LINESTATE, the Link state machine
knows to set the XCVRSELECT and TERMSELECT signals to FS mode (T1).
The standard FS technique of using a pull-up resistor on DP to signal the attach of a FS device is
employed. The Link must then check the LINESTATE signals for SE0. If LINESTATE = SE0 is asserted
BUS
is the +5V power available on the USB cable. Device Reset in
Internal device event initiating the resume
process
Device asserts FS 'K' on the bus to signal
resume request to downstream port
The device releases FS 'K' on the bus. However
by this time the 'K' state is held by downstream
port.
Downstream port asserts SE0.
Latest time at which a device, which was
previously in HS mode, must restore HS mode
after bus activity stops.
demonstrates the timing of the USB3500 control signals during a device attach event. When
Table 7.10 Resume Timing Values (HS Mode)
DESCRIPTION
DATASHEET
41
0 (reference)
T0 < T1 < T0 + 10ms.
T1 + 1.0ms < T2 < T1 + 15ms
T1 + 20ms
T3 + 1.33µs {2 Low-speed bit times}
Figure 7.8
VALUE
indicates that V
Revision 1.0 (06-05-08)
BUS
is