4.12.2 USB 2.0 Interface
The USB1 port of J721E SoC is used for USB 2.0 interface in J721E EVM. The USB1 signals are connected to
upstream port of USB 2.0 Hub (TUSB4041IPAPR). The four downstream ports from USB Hub are connected are
shown below:
• 2 USB ports are terminated to Type A Stacked Connector (AU-Y1008-2)
• 1 USB port is connected to 4 Pin Header (PCIe Card - WiFi/BT)
• 1 USB port is connected to EVM Expansion connector
The reference clock to the USB HUB is provided using 24 MHz crystal and also an optional clock input from the
Peripheral clock generator using a resistor mux. The default clock source is set to crystal.
Figure 4-28. USB Hub Reference Clock Circuit
shows the USB HUB strapping options.
#1
#2
#3
#4
#1
#2
#3
#4
NOTE:
Automatic Charge Mode Disabled
PWRCTL Polarity is Active High
Power Switching and Overcurrent Inputs Supported
Individual Power Control Enabled
Figure 4-29. USB Hub Settings Circuit
And the USB ID pin is pulled low to operate the SoC in Host mode.
To SoM
USB1_ID Pulled low. J721E in Host Mode.
Figure 4-30. USB1 ID Setting for HUB
J721E EVM Hardware Architecture
60
Jacinto7 J721E/DRA829/TDA4VM Evaluation Module (EVM)
SPRUIS4D – MAY 2020 – REVISED MARCH 2022
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