| 摘要 |
In a voltage control circuit ( 100 ), an array ( 500 ) of circuit elements is used to drive a variable capacitor controlling the frequency of a voltage controlled oscillator ( 110 ) (VCO). The array ( 500 ) has a plurality of cells ( 600 ), at least one output, a plurality of coarsesetting inputs ( 383 - 388 ) and a plurality of fine-setting inputs ( 380 - 382 ). Both types of inputs are adapted to enable selectable combinations of the cells ( 600 ). The VCO ( 110 ) is adapted to operate at a plurality of bit-addressable reference frequencies ranging over a plurality of frequency bands. The address control circuit ( 130 ) establishes one of the plurality of frequency bands by controlling the coarse-setting inputs ( 383 - 388 ), and also establishes one of the frequency bands by controlling the fine-setting inputs. In one example, the address control circuit is used to set a frequency band for the VCO circuit ( 100 ) and an analog signal is used to tune to a desired frequency within the band. |
