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Q7-962
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Q7-962 User Manual - Rev. First Edition: 1.0 - Last Edition: 3.1 - Author: S.B. - Reviewed by P.Z Copyright © 2016 SECO S.r.l.
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3.2.1.5
USB interface signals
NXP i.MX6 processor offers four different USB 2.0 controllers.
USB 2.0 controller Core #0 is capable of OTG (On-The-Go) capabilities, capable to work in High Speed (HS), Full Speed (FS) and Low Speed (LS) in Host mode,
and HS/FS in peripheral mode. It is carried out directly to the golden finger connector
USB 2.0 controller Core #1 can work only in Host mode, and can work in HS, FS and LS. It is carried, internally to the upstream port of an SMSC USB2514 USB
2.0 Hub controller, which controls four downstream USB 2.0 compliant ports directly available on golden finger connector (referred as USB ports #0, #2, #3 and
#4)
i.MX6 processor
’
s USB controller cores #2 and #3 are not used by the module.
Here following the signals related to USB interfaces.
/USB_P0-: Universal Serial Bus Port #0 differential pair (coming out from USB2514 Hub Controller Downstream port #1).
/USB_P1-: Universal Serial Bus Port #1 differential pair (directly managed by i.MX6 USB OTG port).
/USB_P2-: Universal Serial Bus Port #2 differential pair (coming out from USB2514 Hub Controller Downstream port #2)
/USB_P3-: Universal Serial Bus Port #3 differential pair (coming out from USB2514 Hub Controller Downstream port #3)
/USB_P4-: Universal Serial Bus Port #4 differential pair (coming out from USB2514 Hub Controller Downstream port #4).
USB_ID: USB ID Input, electrical level +3.3V_S, 10k
Ω
pull-up. This signal must be driven as an open collector signal by external circuitry placed on the carrier
board. It must be tied to GND when USB Port #1 has to be set to work in Host mode. When not driven, USB Port#1 will work in Client mode.
USB_CC: USB Client Connect Pin, electrical level +3.3V_S, 4k7
Ω
pull-up. When USB Port #1 is set to work in Client mode, then this signal shall be used to
inform the USB controller when an external USB Host is connected (signal High) or disconnected (Signal Low).
USB_0_1_OC#: USB Over Current Detect Input. Active Low Input signal, electrical level +3.3V_S with 47k
Ω
pull-up resistor. This pin has to be used for
overcurrent detection of USB Port #0 of
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Q7-962 module
USB_2_3_OC#: USB Over Current Detect Input. Active Low Input signal, electrical level +3.3V_S with 47k
Ω
pull-up resistor. This pin has to be used for
overcurrent detection of USB Ports #2 and #3 of
μ
Q7-962 module
USB_4_5_OC#: USB Over Current Detect Input. Active Low Input signal, electrical level +3.3V_S with 47k
Ω
pull-up resistor. This pin has to be used for
overcurrent detection of USB Port #4 of
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Q7-962 module
Please notice that for correct management of Overcurrent signals, power distribution switches are needed on the carrier board.
For EMI/ESD protection, common mode chokes on USB data lines, and clamping diodes on USB data and voltage lines, are also needed. The schematics in the
following page show an example of implementation on the Carrier Board. In there, USB ports #0, #2, #3 and #4 are carried out to standard USB 2.0 Type A
receptacles, while USB port #1 implements all the circuitry necessary for USB OTG management.
