Circuit board design system, design data analysis method and recording medium with analysis program recorded thereon

A design system equipped with capability to analyze design data for a circuit board having circuit elements placed thereon, comprising:

• a storing section that stores design data representing the circuit board and circuit elements placed thereon,
• a display section that displays a configuration of the circuit board and circuit elements represented by the design data on screen,
• an updating section that updates a configuration of the circuit elements displayed by the display section based on information input from outside,
• a selection section that selects a pair of circuit elements subject to interference analysis among circuit elements placed on the circuit board represented by the design data when the configuration of the circuit elements is updated by the updating section,
• a substitution section that acquires element data concerning the circuit elements selected by the selection section from the design data and generates equivalent circuit data produced by substitution with an equivalent circuit for electromagnetic coupling within the pair of circuit elements based on the element data,
• an analysis section that obtains an amount of interference within the pair of circuit elements by analyzing circuits obtained by reflecting the equivalent circuit data in the circuits of the circuit board represented by the design data, and
• the display section displays data representing the interference amount obtained by the analysis section along with the updated circuit elements when the configuration of the circuit elements is updated by the updating section.

A design system for a circuit board containing a plurality of inductors, comprising:

• a storing section that records design data for the circuit board,
• a selection section that selects a first inductor connected to one of the terminals of a circuit element placed on the circuit board and a second inductor connected to another terminal corresponding to said terminal from the design data,
• a polarity assessment section that provides an assessment as to whether a mutual inductance between the first inductor and the second inductor is positive or negative, and
• a correction section that applies corrections to the design data when the mutual inductance is negative such that an orientation of the first inductor or the second inductor is modified in order to render said mutual inductance positive.

A design system for a circuit board having a plurality of inductors placed thereon, comprising:

• a storing section that stores design data for the circuit board,
• a selection section that selects a first inductor connected to one of the terminals of a circuit element with at least two terminals placed on the circuit board and a second inductor connected to an other terminal corresponding to said terminal from the design data,
• a capacitance calculation section that calculates parasitic capacitance between the first inductor and the second inductor,
• a mutual inductance calculation section that calculates a mutual inductance between the first inductor and the second inductor,
• a frequency calculation section that obtains a resonance frequency of the first inductor and the second inductor, expressed using the parasitic capacitance and the mutual inductance, and
• a correction section that applies corrections to the design data so as to modify a distance between the first inductor and the second inductor in order to match the resonance frequency to the frequency characteristics required for the circuit elements.

An analysis method for, utilizing a computer, analyzing design data, including structure data representing a structure of circuit elements and wiring placed on a circuit board, circuit data representing circuits built from the circuit elements and the wiring, and element data concerning the circuit elements, the analysis method comprising:

• a selection step, in which a selection section provided in the computer selects a pair of circuit elements subject to interference analysis from among circuit elements located on the circuit board represented by the structure data;
• a substitution step, in which a substitution section provided in the computer acquires element data concerning the circuit elements selected in the selection step from the design data and, based on the element data, generates equivalent circuit data representing electromagnetic coupling within the pair of circuit elements using an equivalent circuit;
• and
• an analytical step, in which an analysis section provided in the computer analyzes data obtained by combining the equivalent circuit data and the circuit data in order to calculate an amount of interference within the pair of circuit elements.

A recording medium storing an analysis program directing a computer to carry out processing to analyze design data including structure data representing a structure of circuit elements and wiring placed on a circuit board, circuit data representing circuits built from the circuit elements and the wiring, and element data concerning the circuit elements, the program directing a computer to carry out:

• selection processing, during which a pair of circuit elements subject to interference analysis is selected from among the circuit elements placed on the circuit board represented by the structure data;
• substitution processing, during which element data concerning the circuit elements selected during the selection processing is acquired from the design data and, based on the element data, equivalent circuit data is generated that represents electromagnetic coupling within the pair of circuit elements using an equivalent circuit;
• and
• analytical processing, during which data obtained by combining the equivalent circuit data with the circuit data is analyzed to calculate an amount of interference within the pair of circuit elements.