| 摘要 |
PROBLEM TO BE SOLVED: To reduce chip occupied area and to reduce variation of control gain of a digital control oscillator DCO. SOLUTION: This semiconductor integrated circuit is equipped with the digital control oscillator DCO, the DCO includes oscillation elements NM1, NM2, and a resonance circuit 20, and the resonance circuit 20 includes inductance L11, L12, a variable capacity array CCT 11 for rough adjustment of frequencies, and a variable capacity array CFT 11 for fine adjustment of frequencies. The variable capacity array CCT 11 for rough adjustment includes a plurality of sets of rough adjustment capacity unit cells CCT<0>, CCT<1>, ..., and the variable capacity array CFT 11 for fine adjustment includes a plurality of fine adjustment capacity unit cells CFT<0>, CFT<1>, etc. Capacity values of the plurality of rough adjustment capacity unit cells of the array CCT 11 for rough adjustment are set according to binary weight 2<SP>M-1</SP>, capacity values of the plurality of fine adjustment capacity unit cells of the array CFT 11 for fine adjustment are also set according to binary weight 2<SP>N-1</SP>. COPYRIGHT: (C)2010,JPO&INPIT
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