Embedian SMARC T335 Series, Руководство по конструкции аппаратуры

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SMARC T335x Carrier Board Hardware Design Guide, Document Revision 1.2
3.1.2. Power Control Signals
The input pins listed in the following table are all active low and are meant to
be driven by OD (open drain) devices on the Carrier. The Carrier either floats
the line or drives it to GND. No Carrier pull-ups are needed. The pull-up
functions are performed on the Module. The voltage rail that these lines are
pulled to on the Module varies, depending on the design, and may be 3.3V
or
VDD_IN
.
SMARC Edge Finger I/O Type Power
Rail Description
Pin#
Pin Name
S150 VIN_PWR_BAD# I CMOS VDD_IN Power bad indication from Carrier
board
S154 CARRIER_PWR_ON O CMOS VDD_IN Signal to inform Carrier board
circuits being powered up
P126
RESET_OUT#
O CMOS 3.3V General purpose reset output to
Carrier board.
P127 RESET_IN# I CMOS 3.3V Reset input from Carrier board.
Carrier drives low to force a Module
reset, floats the line otherwise.
Pulled up on Module.
Driven by OD part on Carrier.
S158 VDD_IO_SEL# IO Strap VDD_IN A low logic level on this signal
indicates that the Module VDD_IO
level is configured for the default
level of 1.8V; a high value indicates
that the Module is configured for
3.3V VDD_IO.
Pullup to VDD_IN rail through a
resistance of 100K on module
P128
POWER_BTN#
I CMOS 3.3V Power-button input from Carrier
board. Carrier to float the line in
in-active state. Active low, level
sensitive. It is de-bounced on the
Module
Pulled up on Module.
Driven by OD part on Carrier.