ISP1504A1ETTM STEricsson, ISP1504A1ETTM Datasheet - Page 9

• Manufacturer Part Number: ISP1504A1ETTM
• Manufacturer: STEricsson

Specifications of ISP1504A1ETTM

• Lead Free Status / RoHS Status: Compliant

CD00222688
Product data sheet
7.6.2.1 V
7.6.2.2 Session valid comparator
7.6.2.3 Session end comparator
7.6.1 ID detector
7.6.2 V
7.6.3 SRP charge and discharge resistors
Remark: The ISP1504x1 does not include the 5 V charge pump to power V
The ID detector detects which end of the micro-USB cable is plugged in. The detector
must first be enabled by setting the ID_PULLUP register bit to logic 1. If the ISP1504x1
senses a value on ID that is different from the previously reported value, an RXCMD
status update will be sent to the USB link, or an interrupt will be asserted.
The ISP1504x1 provides three comparators, V
comparator and session end comparator, to detect the V
This comparator is used by hosts and OTG A-devices to determine whether the voltage
on V
comparator is 4.4 V. Any voltage on V
During power-up, it is expected that the comparator output will be ignored.
The session valid comparator is a TTL-level input that determines when V
enough for a session to start. Peripherals, A-devices and B-devices use this comparator
to detect when a session is started. The A-device also uses this comparator to determine
when a session is completed. The session valid threshold of the ISP1504x1 is
V
The ISP1504x1 session end comparator determines when V
session end threshold. The B-device uses this threshold to determine when a session has
ended. The session end threshold of the ISP1504x1 is V
The ISP1504x1 provides on-chip resistors for short-term charging and discharging of
V
restore the V
the previous session by setting the DISCHRG_VBUS register bit to logic 1 and waiting for
SESS_END to be logic 1. Then the B-device charges V
register bit to logic 1. The A-device sees that V
threshold and starts a session by turning on the V
•
•
•
•
•
BUS
A_SESS_VLD
BUS
BUS
The ID detector to sense the ID pin of the micro-USB cable. The ID pin dictates which
device is initially configured as the host and which as the peripheral.
V
detection, SRP and HNP.
Resistors to temporarily charge and discharge V
If the micro-B end of the cable is plugged in, the ISP1504x1 will report that ID_GND is
logic 1. The USB link must change to peripheral mode.
If the micro-A end of the cable is plugged in, the ISP1504x1 will report that ID_GND is
logic 0. The USB link must change to host mode.
BUS
. These are used by the B-device to request a session, prompting the A-device to
BUS
valid comparator
comparators
is at a valid level for operation. The ISP1504x1 threshold for the V
comparators to determine the V
, with a hysteresis of V
BUS
power. First, the B-device makes sure that V
Rev. 04 — 20 May 2010
hys(A_SESS_VLD)
BUS
ISP1504A1; ISP1504C1
BUS
below this threshold is considered invalid.
voltage level. This is required for the V
BUS
BUS
.
BUS
valid comparator, session valid
is charged above the session valid
BUS
power.
BUS
. This is required for SRP.
BUS
B_SESS_END
ULPI HS USB OTG transceiver
by setting the CHRG_VBUS
BUS
voltage level.
BUS
is below the B-device
is fully discharged from
.
© ST-ERICSSON 2010. All rights reserved.
BUS
BUS
BUS
is high
valid
.
9 of 78
BUS