isp1705 NXP Semiconductors, isp1705 Datasheet - Page 50

• Manufacturer Part Number: isp1705
• Description: Ulpi Hi-speed Usb Transceiver
• Manufacturer: NXP Semiconductors

NXP Semiconductors
ISP1705_1
Product data sheet
10.10.1 OTG comparators
10.10.2 Pull-up and pull-down resistors
10.10.3 ID detection
10.10.4 V
10.11 Serial modes
The ISP1705 provides comparators that conform to On-The-Go Supplement to the
USB 2.0 Specification Rev. 1.3 requirements of V
and V
V
are communicated to the link by RXCMDs as described in
comparators is described in
The USB resistors on DP and DM can be used to initiate data-line pulsing SRP. The link
must set the required bus state using the mode settings in
The ISP1705 provides an internal pull-up resistor to sense the state of the ID pin. The
pull-up resistor must first be enabled by setting the ID_PULLUP register bit to logic 1. If
the state of pin ID has changed, the ISP1705 will send an RXCMD or interrupt to the link
by time t
not changed.
A pull-up resistor, R
allowed to charge V
the V
A pull-down resistor, R
whenever the A-device turns off the V
resistor to ensure V
For details, refer to On-The-Go Supplement to the USB 2.0 Specification Rev. 1.3 .
The ISP1705 supports both 6-pin serial mode and 3-pin serial mode, controlled by
bits 6PIN_FSLS_SERIAL and 3PIN_FSLS_SERIAL of the INTF_CTRL register (see
Section
Section 3.10 .
Figure 24
respectively.
A_SESS_VLD
BUS
BUS
B_SESS_END
charge and discharge resistors
11.6). For details, refer to UTMI+ Low Pin Interface (ULPI) Specification Rev. 1.1,
ID
voltage.
. If the link does not receive any RXCMD or interrupt by t
and
. Comparators are described in
Figure 25
. In this data sheet, V
BUS
UP(VBUS)
BUS
DN(VBUS)
Rev. 01 — 13 June 2008
is below V
above the session valid threshold to request the host to turn on
provide examples of 6-pin serial mode and 3-pin serial mode,
, is provided to perform V
Section 11.8
, is provided for a B-device to discharge V
B_SESS_END
BUS
A_SESS_VLD
to
voltage; the B-device can use the pull-down
Section
Section
before starting a session.
A_VBUS_VLD
and V
8.7.2. Changes in comparator values
11.11.
BUS
ULPI Hi-Speed USB transceiver
B_SESS_VLD
pulsing SRP. A B-device is
Section
Table
, V
A_SESS_VLD
15.
ID
10.3.2. Control over
are combined into
, then the ID state has
© NXP B.V. 2008. All rights reserved.
ISP1705
BUS
, V
. This is done
B_SESS_VLD
49 of 89