Patent ID: 7505746

Claim:
An IC which forms a multi-band superheterodyne receiving circuit comprising: a PLL; a first variable divider circuit for dividing an oscillation signal of a VCO forming the PLL by a division ratio n to provide a local oscillation signal; and a mixer circuit for subjecting a received signal to frequency conversion into an intermediate frequency signal by the local oscillation signal, the PLL, the variable divider circuit, and the mixer circuit being formed on one chip, wherein the multi-band receiving circuit is adapted to receive and process a plurality of frequency bands comprising at least a first frequency band and a second frequency band, different from the first frequency band, wherein, to change a reception frequency to a frequency in the first frequency band, the division ratio n of the first variable divider circuit and a division ratio N of a second variable divider circuit forming the PLL are changed, and to change a reception frequency to a frequency in the second frequency band, at least the division ratio N of the second variable divider circuit forming the PLL is changed; wherein the first frequency band has a first frequency step and the second frequency band having a second frequency step, different from the first frequency step.