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# VBAT (optional)
#* this rail provides power for RTC domain of PMIC chip
#* voltage range is TBD2.7 - 5.5V#* current consumption (main is not applied): 7uA typ, 10 uA max.==3.3V power consumption==At the time of this writing (October, 15th 2012) no actual data are availble yet. However since the basic structure of Maya SOM is the same of [[Naon SOM]], [[Power consumption (Naon)|measurements performed on Naon platform]] can be used as a rough estimate of power consumption. In order to address heat management issues properly, please take into account that the majority of power is consumed by the DM814x/AM387x processor. For you convenience here are thermal data of processor's package. Please refer to Texas Instruments Application Report SPRA953B entitled "Semiconductor and IC Package Thermal Metrics" for more details.[[File:CYE-04 Top Hat thermal data.png|300px|center]]A power estimation tool in the form of spreadsheet is also provided by Texas Instruments: http://processors.wiki.ti.com/index.php/DM814x_AM387x_Power_Estimation. ==Sequencing==The following picture shows the power sequence of Maya SOM in the typical scenario. It is assumed that:* carrier board implements power supply unit providing 3.3V power supply voltgage* Maya module in interfaced to generic circuitry (I/O controllers, additional flash memories etc.) operating at 3.3V.[[File:Naon-power-sequence.png|300px|center]]In order to respect required CPU power-up sequence, these steps must be applied:# First monotonic-ramped 3.3V power rail has to be applied to Maya pins named "3.3V"# power management circuitry of Maya will rise EN_BCK2_LS# this signal must be used to enable power of generic circuitry operating at 3.3V (this can be implemented, for example, with a power switch or a DC/DC regulator).
