SC9-TOCCATA • CompactPCI® Serial CPU Board • 11th Generation Intel® Processors
Power Requirements
The SC9-TOCCATA must be supplied with +12V ±10% via its backplane connector P1. A maximum
current value of 6.65A has been defined by the CompactPCI® Serial specification for a card slot.
The maximum current actually required for the SC9-TOCCATA will be by far lower and depends on
the particular processor populated and mezzanine expansion module in use.
For some applications a standby v5V ±10% can be useful in addition, e.g. Wake-on-LAN.
The maximum STANDBY current is defined as 0.95A by the CompactPCI® Serial specification. A
standby power source is an option only and not mandatory for regular operation of the
SC9-TOCCATA.
Main Power Supply Control (PS_ON#)
The SC9-TOCCATA draws its power from the +12V main supply rail defined by the CompactPCI®
Serial specification. The board has been designed to control this main power supply by use of the
signal PS_ON# (backplane connector P1 pin E2). If the system enters the sleep state S5 (Soft Off),
the signal PS_ON# is pulled high, hence the main power supply is switched-off. The SC9-TOCCATA
is held in soft off state until a power management event (e.g. power button event triggered by
the front panel handle) brings back the system to the S0 state.
In order to work as described above and to generate clean signals on PS_ON#, the +5V standby
voltage (STANDBY) mentioned above is necessary. This optional power rail, tied to connector P1
pin B1, is also part of the CompactPCI® Serial specification. The stand-by power rail must be
always switched-on, independent of the state of PS_ON#.
Nevertheless, STANDBY is not mandatory to operate the SC9-TOCCATA. If no standby power is
available, the board creates this voltage from the main power rail. In this case it is important that
the PS_ON# signal is pulled down somewhere in the system or the power supply delivers its
voltage independent of a PS_ON# signal.
Power Supply Status (PWR_FAIL#)
Power supply failures may be detected before the system crashes down by monitoring the signal
PWR_FAIL#. This active low line (connector P1 pin F3) is an addition to the CompactPCI® Serial
specification and may be driven by the power supply. PWR_FAIL# signals the possible failure of
the main supply v12V. On the SC9-TOCCATA the signal PWR_FAIL# is routed to GPP_D7
of the PCH to analyse the state of the power supply unit.
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