SMART Embedded Computing MC1600, Installation And Use Manual

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80 MC1600 Extreme Edge Server Installation and Use (6806870A02B)
System Overview
System Overview
1.14 Power Supply
1.14.1 Power Architecture
The figure below illustrates the high-level power architecture of the Extreme Edge Server.
When -48V power is applied the management power brick is enabled, which generates
3.3V to run the management circuits. At low temperatures, the heater is enabled. Once the
BMC has booted it waits for the power button to be pressed, after which it enables the
payload power POL converters and kicks off the CPU boot process. There is also an auto-
power-on mode where the BMC does not wait for the power button, but automatically
powers up the payload instead.
1.14.2 Payload Power-Up Sequence
When the power button is pressed, the 12V power rail is enabled and the 3.3V and 5V
standby power supplies automatically start up. The ME Engine and the CPU CPLD are
powered at this point.
The next step of the power-up sequence is initiated via a message from the BMC to the
CPU CPLD. This requires a connection between the BMC and the CPU CPLD/ME via
SMBus. The CPU CPLD implements registers for power up control. When a message to
power one of the CPUs is sent by the BMC via SMBus to these power control registers, the
CPU power-up sequence is initiated. The power-up sequence continues until the S0 state
is reached.
The processors on the card can be powered up/down independently. This requires a dual
power-up state machine design in the CPU CPLD.
Figure 1-9 Power Architecture