| 摘要 |
PROBLEM TO BE SOLVED: To carry out confirmation of impedance consistency of a signal pattern and a transmission line at high speed on the basis of a relational expression of output impedance and characteristic impedance. SOLUTION: The signal integrity confirming method has an output impedance DB 2 storing, precedently calculated output impedance from a device model DB 1, per LSI, and a terminating resistor value DB 3. Characteristic impedance of a signal pattern connected to an output buffer is calculated from a layer structure including a pattern width and a thickness between layers of a printed circuit board. If it is connected to the signal pattern by only the output buffer, a value of output impedance extracted from the output impedance DB is compared with the calculated value of the characteristic impedance of the signal pattern. If a terminating resistor is connected, a value of adding its terminating resistor value and the output impedance of the output buffer is compared with a value of the characteristic value of the signal pattern, and it is confirmed whether it is within a conformable range. COPYRIGHT: (C)2007,JPO&INPIT
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