4 motherboard power consumption – Endura RADISYS KP915GV User Manual
Page 48
KP915GV Product Manual
48
•
On-chip Clock Generator:
•
Generates 48 MHz clock
•
Generates 32.768 KHz internal clock
•
VSB3 powered
•
Based on the 14.31818 MHz clock input
•
Protection
•
All pins are 5V tolerant and back-drive protected (except LPC bus pins)
•
High ESD protection of all the pins
•
Pin multiplexing selection lock
•
Configuration register lock
•
Testability
•
XOR tree structure
•
Includes all the pins (except supply and analog pins)
•
Selected at power-up by strap input (TEST)
•
TRI-STATE pins, selected at power-up by strap input (TRIS)
•
Power Supply
•
3.3V supply operation
•
Separate pin pairs for main (VDD3) and standby (VSB3) power supplies
•
Backup battery input (VBAT) for SWC indications
•
Low standby power consumption
•
Very low power consumption from backup battery (less than 0.5 μA)
•
Package 128-pin PQFP
3.4 Motherboard
Power
Consumption
The motherboard power consumption is highly dependent on the processor, memory and devices
attached and also on the software that is running and the power state that the board is in. The
figures given below are a guide to the power requirements to expect under selected conditions.
They should not be interpreted as maximum requirements. The figures are based on
measurements of a real system configured as shown in the following table.
It is recommended that the board be used with a power supply that supports a minimum
current load of 0.3A or less on the 5V supply rail and 2A or less on the 3.3V supply rail.
This board with CPU and memory may draw as little as 400mA of 5V and 2A of 3.3V during
start-up (increases depend on installed devices). The power supply under consideration
must be verified as compatible with the projected total system start-up loads for these
supply rails. If the power supply minimum current level requirements are not at or below the
level of current loads that are actually drawn, unpredictable start-up operation may result,
such as the power supply latching off. If this occurs, the AC input to the power supply must
be removed and re-attached or the power supply switch cycled off and on, in order to turn
the system back on.