Method and device for electromagnetic field analysis of circuit board, and circuit board and its design method

An apparatus for analyzing an electromagnetic field of a circuit board based on shapes of conductor patterns and signal analysis conditions comprising:

• means for setting up initial shapes of conductor patterns in each layer of a multilayer circuit board;
• means for setting up initial ports for input or output of an external signal in each conductor pattern;
• means for dividing two-dimensionally the multilayer circuit board into a plurality of areas;
• means for setting up additive ports on edges of the conductor pattern which is created by area-division;
• means for setting up individual analysis conditions for the initial ports and the additive ports, respectively;
• means for performing an electromagnetic analysis of the multilayer circuit board by the divided area, based on the analysis conditions;
• and
• means for integrating results of the electromagnetic analysis over each of the divided areas, thereby obtaining results of the electromagnetic analysis over the whole circuit board.

A circuit board with a rectangular shape comprising:

• a plurality of layers having conductor patterns;
• and
• a plurality of spiral inductance patterns provided in the conductor patterns;
• wherein three out of the plurality of spiral inductance patterns are located on at least three of corner portions of the circuit board.

A method for designing a circuit board including a plurality of layers having conductor patterns in which a plurality of spiral inductance patterns are provided, including steps of:

• dividing the circuit board into a plurality of divided areas using a dividing line;
• and
• designing a circuit pattern over each of the divided areas using simulation,
• wherein the dividing line is set up so as not to cut off two or more out of the plurality of spiral inductance patterns provided in the circuit board.