SBC-C61
SBC-C61 User Manual - Rev. First Edition: 1.0 - Last Edition: 1.1 - Author: S.B. - Reviewed by N.P. - Copyright © 2021 SECO S.p.A.
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3.3.9
USB Connectors
The i.MX8M Mini processor offers a total amount of two USB 2.0 OTG interfaces
The first USB OTG interface is carried out to a standard micro-AB connector, described in the table on
the left, type ZX62-B-5PA.
Depending on the needed use of the system, it is necessary to connect micro-A or micro-B USB
cables to connector CN36.
A micro-A USB cable has to be used when the system has to work in Host mode. In this case, USB_VBUS is a power
output of SBC-C61 Board for the connected device.
When a micro-B USB cable is used, its USB_ID pin is floating; this way, the board acknowledges that it must configure
itself to work as a Client. In this case, USB_VBUS is an input of the carrier board from the external Host.
This interface is switched, through a dedicated USB switch SW controlled, with the USB interface necessary to manage
the optional on-board modem described at par 3.3.2.
U/USB_OTG1-: USB OTG Port #1 differential pair.
USB_OTG1_VBUS: USB voltage rail. It is an input for USB port working in Client mode, an output for Host mode.
USB_ID: Client/Host identification signal. This signal is high when the USB port works in client mode, is low when works in Host mode. VDD_3V3 electrical level with
a 10K
Ω
pull-up resistor.
Please be aware that the USB Host mode on CN36 is allowed only if the SC61 board is not equipped with the optional Modem module.
The second USB interface is carried to a Microchip USB2514 USB2.0 Hub, which makes available four USB
2.0 downstream host ports.
The first and second downstream ports are carried to a double connector, CN48, which is a standard double
USB Type A socket, shielded.
Since this connector is a standard type-A receptacle, it can be connected to all types of USB 1.1 / USB 2.0
devices using standard-A USB 2.0 plugs
USB1+/USB1-: USB Hub Downstream port #1 differential pair.
USB2+/USB2-: USB Hub Downstream port #2 differential pair.
USB micro-AB Connector CN36
Pin Signal
1
+5V_USB_OTG
2
USB_OTG1-
3
U
4
USB_ID
5
GND
Dual USB 2.0 Type-A Socket CN48
Pin Signal
Pin
Signal
1
+5V
USB1
5
+5V
USB2
2
USB1-
6
USB2-
3
USB1+
7
USB2+
4
GND
8
GND
