USB3450 Standard Microsystems Corporation, USB3450 Datasheet - Page 35

• Manufacturer Part Number: USB3450
• Description: Hi-speed USB HOST OR Device PHY WITH Utmi+interface
• Manufacturer: Standard Microsystems Corporation

Hi-Speed USB Host or Device PHY With UTMI+ Interface
Datasheet
SMSC USB3450
7.10
TERMSELECT
XCVRSELECT
SUSPENDN
OPMODE 1
OPMODE 0
Notes:
■
■
■
If reset is entered from a suspended state, the internal oscillator and clocks of the transceiver are
assumed to be powered down.
chirp generated by the device.
When reset is entered from a suspended state (J to SE0 transition reported by LINESTATE),
SUSPENDN is combinatorially negated at time T0 by the Link. It takes approximately 5 milliseconds
for the transceiver's oscillator to stabilize. The device does not generate any transitions of the CLKOUT
signal until it is “usable” (where “usable” is defined as stable to within ±10% of the nominal frequency
and the duty cycle accuracy 50±5%).
The first transition of CLKOUT occurs at T1. The Link then sets OPMODE to Disable Bit Stuffing and
NRZI encoding, XCVRSELECT to HS mode, and must assert a Chirp K for 66000 CLKOUT cycles to
ensure a 1ms minimum duration. If CLKOUT is 10% fast (66MHz) then Chirp K will be 1.0ms. If
CLKOUT is 10% slow (54 MHz) then Chirp K will be 1.2ms. The 5.6ms requirement for the first
CLKOUT transition after SUSPENDN, ensures enough time to assert a 1ms Chirp K and still complete
before T3. Once the Chirp K is completed (T3) the Link can begin looking for host chirps and use
CLKOUT to time the process. At this time, the device follows the same protocol as in
Detection Handshake – HS Downstream Facing Port"
HS Detection Handshake – Suspend Timing
TXVALID
DP/DM
CLK60
Figure 7.6 HS Detection Handshake Timing Behavior from Suspend
T0 may be up to 4ms after HS Reset T0.
The Link must use LINESTATE to detect the downstream port chirp sequence.
Due to the assertion of the HS termination on the host port and FS termination on the device port,
between T1 and T7 the signaling levels on the bus are higher than HS signaling levels and are
less than FS signaling levels.
time
J
T0
SE0
Figure 7.6
CLK power up time
DATASHEET
35
shows how CLKOUT is used to control the duration of the
for completion of the High Speed Handshake.
T1
T2
Device Chirp K
T3
T4
Look for host chirps
Revision 0.1 (05-11-05)
Section 7.9, "HS