emCON-MX8MM - Hardware Manual (Rev1)
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4.20
Reset
There are several ways for issuing a reset signal:
•
A voltage monitor checks the board voltages. If one voltage is out of tolerance, a module
reset is asserted.
•
The active low signal RESI# and the signal JTAG_RESI# at the emCON connector can assert a
reset.
•
A processor internal SW reset is available at a processor pin. In this case the RESO# pin is
asserted if a SW reset is asserted.
All resets are hardware resets of the whole board. All resets except the internal SW reset issue a
processor cold reset. The internal SW reset issues a processor warm reset.
The duration of the reset signal is min.120ms. For resetting external devices, the reset signal is
available as an output (RESO#) at the emCON connector.
4.21
Power Supply
The typical power consumption is depending on the running software tasks and the external
devices which must be supplied via the emCON connector.
The onboard required voltages for the processor and the other parts are generated on board via a
Power Management (PMIC) chip.
The voltages generated by the PMIC can be configured via the I²C interface. During operation, the
voltages can be varied depending on core frequencies and temperature.
4.21.1
Signal Description
VCC_STANDBY & VCC_5V:
The 5v power supply is divided into two voltage areas. VCC_Stby is used to power up and keep the
PMIC, as well as the most important voltages of the CPU, alive during power down states. +5V0DC
is the main supply and used to supply the board in the running state.
If power management is used, the +5V0DC can be disabled in deep power down states. The
disabling can be done for example with a mosfet circuit at the baseboard. To control the mosfet,
the signal SUSPEND# is available at the emCON interface. Example schematics are also available.
VCC_Stby has to be kept on all the time.
If no power management is needed, VCC_STANDBY and +5V0DC can be both connected to 5V
directly.
