Doc. No: Unex-QSG-21-003
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© 2023 Unex Technology Corporation – Company Confidential
9.12.2.
Host GPIO control
When the mPCIe Pin 46 (BOOTSTRP) connects to a host system GPIO, and the
BOOTSW (SW1.8) is kept at ON position, the host system GPIO controls the boot mode.
•
BOOTSTRP LO: Normal boot (boot from NAND)
•
BOOTSTRP HI: Firmware upgrade (boot from USB0, DFU mode)
10.
Dimensions and Weight
The SOM-352 module follows the PCIe full-mini card form factor, but 8.5mm wider than
the standard 30mm width. When designing a system board, at least 3mm clearance on
both left and right side is needed to avoid component interference. It is also recommended
to reserve 13mm as total height limitation. Please refer to
PCI Express Mini Card
Electromechanical Specification 2.0/2.1
for more detailed guidelines.
It is recommended to use a mini PCIe connector with 4mm stack height, leaving 1.5mm
space between the SOM-352 PCB and the system board. This space can later be filled with
silicone thermal conductive pad to help dissipate the heat generated by SOM-352 to the
system board PCB. User can choose
TE 2041119-1
as a candidate for such a mini PCIe
connector.
