distrib/docxml2/text/common/formats/power_supplies.xml

   1
   2 <section niv='3'><title>Defining Power Supplies</title>
   3 <p>Special attention should be paid to the definition of power supply and ground nodes
   4 (<f>avtVddName</f>, <f>avtVssName</f> and <f>simPowerSupply</f> variables).
   5 Indeed, the disassembly process is heavily dependant on the naming of those nodes, as the algorithm is looking
   6 for current paths towards power supply and ground. Bad specification of these nodes can lead to the construction of
   7 an exponential number of wrong current paths. Power supply and ground definition is the first thing to check if the
   8 disassembly process seems to loop infinitely.</p>
   9 <p>&tool; also supports V cards for the definition of power supply and ground nodes. One can distinguish between two
  10 cases:</p>
  11 <p>The power supply and ground node appear on the interface of the <f>.SUBCKT</f>, and the subcircuit is instanciated.
  12 The V cards should refer to the names used in the instanciation:</p>
  13 <code>
  14 <cl>Vsupply vdd gnd DC 1.2V</cl>
  15 <cl>Vground gnd 0   DC 0V</cl>
  16 <cl>   </cl>
  17 <cl>.SUBCKT my_design a b c vdd_int gnd_int</cl>
  18 <cl>...   </cl>
  19 <cl>.ENDS my_design   </cl>
  20 <cl>   </cl>
  21 <cl>X0 a b c vdd gnd my_design</cl>
  22 </code>
  23
  24
  25 <p>The power supply and ground node does not appear on the interface of the <f>.SUBCKT</f>, or the subcircuit is not
  26 instanciated. The V cards should refer to the names used within the subcircuit, or appearing on the interface of
  27 the <f>.SUBCKT</f>, together with <f>.GLOBAL</f> statements:</p>
  28 <code>
  29 <cl>.GLOBAL vdd gnd</cl>
  30 <cl>   </cl>
  31 <cl>Vsupply vdd gnd DC 1.2V</cl>
  32 <cl>Vground gnd 0   DC 0V</cl>
  33 <cl>   </cl>
  34 <cl>.SUBCKT my_design a b c vdd gnd</cl>
  35 <cl>...   </cl>
  36 <cl>.ENDS my_design   </cl>
  37 </code>
  38 </section>