Dacu for the Diva SOM

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Info Box
Dacu-top-view.png Applies to Dacu
Diva-am335x-overview.png Applies to Diva

Introduction[edit | edit source]

When used in combinaton with Diva SOM, DACU requires the use of DivaEVB-Lite acting as adaptation board. The overall system looks like the following picture and it is composed by

  • Diva SOM
  • DivaEVB-Lite
  • DACU.


In order to make DACU compatible with this configuration, some additional wired connections are required, as detailed in the schematics. Following sections explains in more detail these issues.

Power supply[edit | edit source]

This is the power-up sequence of the whole system (it matches Diva recommended power-up sequence):

  1. power supply or wall adapter connected to DACU's JP2 is turned on
  2. DACU's U15 DC/DC PSU is turned on; since the output of this DC/DC is connected to DivaEVB-Lite's VREG rail, Diva SOM is powered
  3. Diva performs its own power-on sequence
  4. DivaEVB-Lite's U4 linear regulator is enabled by Diva
  5. DivaEVB-Lite's 3.3V rail raises; since this rail is connected to DACU's ENA_3.3V, DACU's U16 DC/DC PSU is enabled and DACU's circuitry interfacing processor's I/O is powered

DACU's USB host port[edit | edit source]

DACU's USB host port power is controlled by Micrel MIC2026 Dual-Channel Power Distribution Switch (U7). B channel of this swith is associated to USB host port. In order to control this channel, Diva's USB1_DRVVBUS and VUSB_VBUS1 signals are connected to ENB and FLGB pads respectively.