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SUS_S3#/PS_ON#
The SUS_S3#/PS_ON# (pin A15 on the COM Express connector) signal is an active-low output that can be used to turn on the main outputs of
an ATX-style power supply. In order to accomplish this the signal must be inverted with an inverter/transistor that is supplied by standby voltage
and is located on the carrier board.
PWRBTN#
When using ATX-style power supplies PWRBTN# (pin B12 on the COM Express connector) is used to connect to a momentary-contact, active-
low debounced push-button input while the other terminal on the push-button must be connected to ground. This signal is internally pulled
up to 3V_SB using a 10k resistor. When PWRBTN# is asserted it indicates that an operator wants to turn the power on or off. The response to
this signal from the system may vary as a result of modifications made in BIOS settings or by system software.
Power Supply Implementation Guidelines
Input power of 4.75 - 20 volt is the sole operational power source for the conga-MA5. The remaining necessary voltages are internally generated
on the module using onboard voltage regulators. A carrier board designer should be aware of the following important information when
designing a power supply for a conga-MA5 application:
•
It has also been noticed that on some occasions, problems occur when using a power supply that produces non monotonic voltage when
powered up. The problem is that some internal circuits on the module (e.g. clock-generator chips) will generate their own reset signals
when the supply voltage exceeds a certain voltage threshold. A voltage dip after passing this threshold may lead to these circuits becoming
confused resulting in a malfunction. It must be mentioned that this problem is quite rare but has been observed in some mobile power
supply applications. The best way to ensure that this problem is not encountered is to observe the power supply rise waveform through
the use of an oscilloscope to determine if the rise is indeed monotonic and does not have any dips. This should be done during the power
supply qualification phase therefore ensuring that the above mentioned problem doesn't arise in the application. For more information, see
the “Power Supply Design Guide for Desktop Platform Form Factors” document at www.intel.com.
Inrush and Maximum Current Peaks on VCC_5V_SB and VCC
The inrush current on the conga-MA5 VCC_5V_SB power rail can go up as high as 3.58 A and as high as 11.5 A on VCC power rail (12 V) within
a short time (approx. 150μs) and with a voltage rise time of 100μs. Sufficient decoupling capacitance must be implemented on the carrier board
to ensure proper power-up sequencing.
5.15
Power Management
ACPI 5.0 compliant with battery support. Also supports Suspend to RAM (S3).
