VICOR PI33 EVAL1 Series, Руководство пользователя

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UG:309 Page 18
Configuration Example – Enable Polarity
Figure 25 shows the complete procedure for changing the enable polarity along with the I 2 C™ bus
capture of all of the commands required to make the changes using Buck GUI or some other generic
software. Since the enable polarity is not changed until AFTER the burn is completed, always use the
default polarity of the signal before the burn process to enable and disable the target PI33xx‑xx. It
should be pointed out that the SYN[3:0] register had already been programmed to “0010” on the
PI33xx‑xx target prior to the enable polarity change. Note that the first two bus transactions occur when
the target PI33xx‑xx is enabled and the final transaction occurs when it is disabled. Failure to follow
this exact sequence will prevent successful storage of the desired configuration settings. If an error
message occurs or the incorrect results are obtained, refer to the section titled “Error Messages” for
more information.
Figure 25
Changing EN_POL register to
“1” with SYN[3:0]
programmed to “0010”