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TABLE OF CONTENTS 
1.  INTRODUCTION ............................................................................................................................3 
1.1  Purpose ...................................................................................................................................................... 3 
2.  MC9190 EXTERNAL POWER PIN ..............................................................................................4 
2.1  Background ............................................................................................................................................... 4 
2.2  Theory of Operation .................................................................................................................................. 4 
3.  DESIGN .............................................................................................................................................7 
3.1  Software Design ........................................................................................................................................ 7 
3.1.1  Sample code to enable external power ...........................................................................................7 
3.1.2  State at EXP Open and Close .........................................................................................................8 
3.1.3  Boot up state...................................................................................................................................8 
3.1.4  Suspend and Resume ......................................................................................................................9 
3.2  Test Application ........................................................................................................................................ 9 
3.2.1  Open and Close buttons in the COM Block ...................................................................................9 
3.2.2  Open and close buttons in the Power Block ...................................................................................9 
3.2.3  Enable and Disable buttons in the Power block ............................................................................9 
3.2.4  Blank text box and the “X” button .................................................................................................9 
4.  NOTES ............................................................................................................................................ 10 
 
 
TABLE OF FIGURES 
Figure 1 – MC9190 bottom port ............................................................................................................. 4 
Figure 2 - Block diagram.......................................................................................................................... 6 
Figure 3 - Test Application ...................................................................................................................... 9 
LIST OF TABLES 
Table 1: MC9190 Bottom Port Pin-Outs ................................................................................................. 5