User's Manual

DRAFT
4: VAM-CM interfaces
4.4: VAM-CM Power Management Handling
The VAM-CM power management handling is based on VAM-CM control interface, UART or USB.
This is required to put CM in low power mode to reduce CM power consumption.
4.4.0.1:VAM-CM USB interface PM Handling
In the VAM-CM USB control interface, core module (CM) supports USB suspend/resume feature as
per USB2.0 standards to put in low power mode. By default low power mode is disabled in CM and
CM can be put into low power mode based on USB suspend signal and wakeup based on resume
signal, seeReferences on page 5 section 7.1.7.6 and 7.1.7.7. Without handling USB
suspend/resume the CM will not enter low power mode and hence overall current consumption will
be more. It is recommended that the VAM should implement USB suspend/resume feature to put CM
in low power mode and wakeup from low power mode.
4.4.0.2:VAM-CM UART interface PM Handling
In VAM-CM UART control interface, core module (CM) low power mode (sleep) is by default enabled
and VAM can get sleep state and wakeup from sleep state using VAM_CM_SLEEP and VAM_CM_
WAKEUPsignals. VAM can check CM sleep state using VAM_CM_NSLEEP signal, high=Active and
low=sleep. VAM need to check VAM_CM_SLEEP signal before sending any data to CM and if this
signal is low then set VAM_CM_WAKEUPsignal high for 100mSec to wakeup CM and ready to
process data. See Table 9 for Sleep and Wake-up signal details.
4.5: Mechanical interface
Mechanical dimensions and mounting points are shown in Figure 11 - Figure 13 . VAM-CM can be
mounted with four 2,5mm screws from the module corners. 5mm extension towers are required to
mount VAM-CM so that tightening the screws does not introduce any forge to components and shield
can soldered on the board.
Figure 11. Front view dimensions
20:GSPS Core Module 2.0 VAM-CM HW Description
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