Printed circuit board design support system, printed circuit board design method and storage medium storing control program for same

A printed circuit board (PCB) design support system comprising:

• an inputting means to input an information about ground plane structure, power plane structure and layout of a PCB including information about positions of mounting active elements and at least one decoupling capacitor;
• a model building means to build a circuit model expressed by an equivalent circuit for calculating, using input said information, voltage distribution between said ground plane and said power plane;
• a calculating means to select a specified frequency and to calculate voltage distribution occurring at said specified frequency between said ground plane and said power plane;
• a displaying means to display said obtained voltage distribution in a form of a two-dimensional voltage distribution map in a manner to correspond to a shape of said PCB;
• a storing means to store the result obtained from operations;
• an extracting means to extract a position of said via-hole straddling said ground plane and said power plane based on input said information about signal wiring including layout information, a setting means to set said extracted position of said via-hole to said voltage distribution map of said calculated voltage distribution occurring between said ground plane and said power plane and/or to display said extracted position of said via-hole on said voltage distribution map and a warning means to issue a sign that gives warning to any of said via-hole disposed in a region here a voltage is at a high level.

A PCB support system comprising:

• an inputting means to input information about ground plane structure, power plane structure and layout of a PCB including information about positions of mounting active elements and at least one decoupling capacitor;
• a model building means to build a circuit model for calculating, using input said information, distribution of currents flowing on both said ground plane and said power plane;
• a calculating means to select a specified frequency and to calculate distribution of currents flowing, at said specified frequency, in two directions in a manner being parallel to ends of said ground plane and said power plane, on both said ground plane and said power plane;
• a displaying means to display separately each of said current distributions obtained in said two current flowing directions in a form of a two-dimensional current distribution map in a manner to correspond to a shape of said PCB;
• and
• a storing means to store results obtained from operations,
• wherein the model building means expresses the circuit model as a planar matrix of nodes, each of the adjacent nodes being connected by an inductor and a resistor, and each of the nodes being further connected to a grounded capacitor.

A method of designing a PCB comprising steps of:

• inputting information about ground plane structure, power plane structure and layout of a PCB including information about positions of mounting active elements and at least one decoupling capacitor;
• building a circuit model for calculating, using input said information, currents flowing on both said ground plane and said power plane,
• the circuit model being a planar matrix of nodes, each of the adjacent nodes being connected by an inductor and a resistor, and each of the nodes being further connected to a grounded capacitor;
• selecting a specified frequency and calculating distribution of current flowing in two directions in a manner being parallel to ends of said ground plane and said power plane, at said specified frequency, on both said ground plane and said power plane;
• displaying separately each of said current distributions obtained in said two current flowing directions in a form of a two-dimensional current distribution map in a manner to correspond to a shape of said PCB;
• and
• deciding, using said current distribution map, a position of installing wiring in a layer disposed between said ground plane and said power plane.

A machine-readable storage medium storing a control program used for designing a PCB, wherein said control program causes a computer to carry out steps of:

• inputting information about ground plane structure, power plane structure and layout of a PCB including information about positions of mounting active elements and at least one decoupling capacitor;
• building a circuit model for calculating, using input said information, voltage distribution between said ground plane and said power plane, the circuit model being a planar matrix of nodes, each of the adjacent nodes being connected by an inductor and a resistor, and each of the nodes being further connected to a grounded capacitor;
• selecting a specified frequency and of calculating voltage distribution occurring at said specified frequency between said ground plane and said power plane,
• the calculating of voltage distribution including adding a corner resistor at a corner of the matrix, then driving the matrix with a voltage source at the selected frequency, and calculating the voltage at each node of the matrix;
• displaying said obtained voltage distribution in a form of a two-dimensional voltage distribution map in a manner to correspond to a shape of said PCB;
• and
• deciding, using said voltage distribution map, a position of disposing a via-hole formed in a manner to straddle said ground plane and said power plane.

A machine-readable storage medium storing a control program used for designing a PCB, wherein said control program causes a computer to carry out steps of:

• inputting information about ground plane structure, power plane structure and layout of a PCB including information about positions of mounting active elements and at least one decoupling capacitor;
• building a circuit model for calculating, using input said information, distribution of currents flowing on both said ground plane and said power plane, the circuit model being a planar matrix of nodes, each of the adjacent nodes being connected by an inductor and a resistor, and each of the nodes being further connected to a grounded capacitor;
• selecting a specified frequency and calculating distribution of currents flowing, at said specified frequency, in two directions in a manner being parallel to ends of said ground plane and said power plane, on both said ground plane and said power plane;
• displaying separately said obtained two current distributions obtained in said two current flowing directions in a form of a two-dimensional current distribution map in a manner to correspond to a shape of said PCB;
• and
• deciding, by using said current distribution map, a position of installing wiring in a layer disposed between said ground plane and said power plane.

A PCB design support system provided with a control program for designing a PCB, wherein said control program causes a computer to carry out steps of:

• accepting input information about ground plane structure, power plane structure and layout of a PCB including information about positions of mounting active elements and at least one decoupling capacitor;
• building a circuit model for calculating, using input said information, voltage distribution between said ground plane and said power plane, the circuit model being a planar matrix of nodes, each of the adjacent nodes being connected by an inductor and a resistor, and each of the nodes being further connected to a grounded capacitor;
• selecting a specified frequency and of calculating voltage distribution occurring at said specified frequency between said ground plane and said power plane;
• displaying said obtained voltage distribution in a form of a two-dimensional voltage distribution map in a manner to correspond to a shape of said PCB;
• and
• deciding, using said voltage distribution map, a position of disposing a via-hole formed in a manner to straddle said ground plane and said power plane.

A PCB design support system provided with a control program for designing a PCB, wherein said control program causes a computer to carry out steps of:

• accepting input information about ground plane structure, power plane structure and layout of a PCB including information about positions of mounting active elements and at least one decoupling capacitor;
• building a circuit model for calculating, using input said information, distribution of currents flowing on both said ground plane and said power plane, the circuit model being a planar matrix of nodes, each of the adjacent nodes being connected by an inductor and a resistor, and each of the nodes being further connected to a grounded capacitor;
• selecting a specified frequency and calculating distribution of currents flowing, at said specified frequency, in two directions in a manner being parallel to ends of said ground plane and said power plane, on both said ground plane and said power plane;
• displaying separately said obtained two current distributions obtained in said two current flowing directions in a form of a two-dimensional current distribution map in a manner to correspond to a shape of said PCB;
• and
• deciding, by using said current distribution map, a position of installing wiring in a layer disposed between said ground plane and said power plane.