Patent ID: 7199577

Claim:
A systematic method for theoretically assessing the effectiveness of decoupling capacitance in noise suppression in a printed circuit board having at least one DC power supply by analysis of anti-resonant frequencies and discrete capacitor component values, comprising: inputting circuit board parameters along with values for non-ideal discrete capacitors provided in the board design for each power supply in the board, including capacitor capacitance, resistance and inductance values; approximating the series resonance for each DC power supply circuit on the board; approximating the parallel resonance for each DC power supply circuit on the board; approximating impedance for each power supply circuit on the board at each anti-resonant frequency; totaling the impedance from each power supply circuit on the board to derive total impedance values for the board that have been characterized at the relevant anti-resonant frequencies; outputting the derived total approximated impedance values at the anti-resonant frequencies; comparing the derived theoretical board impedance values at the relevant anti-resonant frequencies with a target impedance representing a desired design criteria for the printed circuit board; and making a determination of compliance or non-compliance based on the comparison with the target impedance; and outputting an indication of compliance or non compliance through an output device.