isp1301 NXP Semiconductors, isp1301 Datasheet - Page 24

• Manufacturer Part Number: isp1301
• Description: Universal Serial Bus On-the-go Transceiver
• Manufacturer: NXP Semiconductors

Philips Semiconductors
ISP1301_3
Product data sheet
command to the ISP1301 to assert the DP pull-up. An alternative method is for the
A-device transceiver to automatically assert the DP pull-up after detecting an SE0 from
the B-device.
The sequence of events is: After finishing data transfers between the A-device and the
B-device and before suspending the bus, the A-device sends SOFs. The B-device
receives these SOFs, and does not transmit any packet back to the A-device. During this
time, the A-device sets the BDIS_ACON_EN bit in the ISP1301. This enables the
ISP1301 to look for SE0 whenever the A-device is not transmitting (that is, whenever the
OE_N/INT_N pin of the ISP1301 is not asserted). After the BDIS_ACON_EN bit is set, the
A-device stops transmitting SOFs and allows the bus to go to the idle state. If the B-device
disconnects, the bus goes to SE0, and the ISP1301 logic automatically turns on the
A-device pull-up.
Rev. 03 — 21 February 2006
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
USB OTG transceiver
ISP1301
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