PCM-065/phyCORE-i.MX8X System on Module
L-864e.A1
© PHYTEC America LLC, 2021
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Pin Descriptions
Most of the processor signals extend to Samtec Connectors (0.5mm) lining two sides of the module (referred to
as the phyCORE-Connector). This allows the phyCORE-i.MX8X SOM to be inserted into any target application
like a "big chip".
The numbering scheme for the phyCORE-Connector is based on a two-dimensional matrix in which column
positions are identified by a letter and row position by a number. Pin A1, for example, is located in the top left
hand corner of the matrix looking down through the top of the SOM. The pin number increases for each
subsequent pin along the connector. Lettering of the pin connector columns progress alphabetically from left to
right for each connector (refer to
The numbered matrix can be aligned with the phyCORE-i.MX8X SOM (viewed from above; phyCORE-Connector
pointing down) or with the socket of the corresponding phyCORE Carrier Board/user target circuitry. The
numbering scheme is always in relation to the PCB as viewed from above, even if all connector contacts extend
to the bottom of the module.
illustrates the numbered matrix system. It shows a phyCORE-i.MX8X SOM with phyCORE Connectors
on its underside (defined with dotted lines) as it would be mounted on a Carrier Board. In order to facilitate
understanding of the pin assignment scheme, the diagram presents a cross-view of the phyCORE-module
showing these phyCORE-
Connectors mounted on the underside of the module’s PCB.
provides an overview of the pinout of the phyCORE-Connector with signal names and descriptions
specific to the phyCORE-i.MX8X SOM. It also provides the appropriate voltage domain, signal type (ST) and a
functional grouping of the signals. The signal type also includes information about the signal direction.
CAUTION:
The NXP Semiconductor i.MX8X is a multi-voltage operated microprocessor and as such, special attention
should be paid to the interface voltage levels to avoid unintentional damage to the microprocessor and other
on-board components.
Please ensure that all module connections do not exceed their expressed maximum voltage or current. As
damage from improper connections varies according to use and application.
It is the user's responsibility to take appropriate safety measures to ensure that the module
connections are protected from overloading through connected peripherals.
Please refer to the NXP Semiconductor
i.MX8X Processor Reference Manual
for details on the functions and
features of processor signals in addition to maximum operating characteristics.
CAUTION:
It is mandatory to avoid driving external power to the IO pins of the phyCORE-i.MX8X SOM when the module
itself is not powered. This may cause current to flow through the IO pins before the processor is properly
powered, potentially resulting in damage or unknown behavior after power-up or reset. Therefore, PHYTEC
recommends NOT powering external peripherals and circuits that directly interface with the phyCORE-i.MX8X
SOM IOs until their respective voltage domains are powered. The peripheral carrier board power should be
switched on/enabled by the X_PGOOD signal. X_PGOOD is a 3.3V level signal that is driven high once the
PMIC has finished its power sequencing and the SOM has been powered on. This should be used to sequence
the baseboard power supplies (3.3V, 1.8V, etc.). This ensures that the IO domains on the SOM are powered
before any external circuits or peripherals drive power to the processor pins. To accomplish this, it is
recommended to either implement a separate 3.3V power supply that is dedicated to the VCC input of the
SOM or integrate load switches to turn on the peripheral voltage rails after the SOM has finished powering up.
