| 摘要 |
PROBLEM TO BE SOLVED: To accurately meet the resistance value of a replica resistance for adjusting a terminating resistance with an external reference resistance without depending upon a parasitic resistance. SOLUTION: Voltage measurement circuits 11 and 12, a determination circuit 13 and an adjustment code generation circuit 14 are provided in a terminating resistance adjustment circuit 101 provided in an LSI 100. One end of a replica resistance Rrep is connected to a power terminal VDD, and the other end is connected to the voltage measurement circuit 11 and also connected to an external reference resistance Rref. One end of the reference resistance Rref is connected to the voltage measurement circuit 12. Measurement results of the voltage measurement circuit 11 and the voltage measurement circuit 12 are inputted to the determination circuit 13 to be compared, and a determination result code formed on the basis of the result is outputted to the adjustment code generation circuit 14. The replica resistance Rrep is adjusted by an adjustment code outputted by the adjustment code generation circuit 14. COPYRIGHT: (C)2009,JPO&INPIT
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