发明名称 |
METHOD AND CIRCUIT FOR AUTOMATIC, HIGH-PRECISION FREQUENCY FINE-TUNING |
摘要 |
Prior art analog automatic frequency fine-tuning systems are inaccurate and cannot be completely integrated on account, for instance, of the resonance circuit they require. Prior art digital automatic frequency fine-tuning systems can be highly accurate, but require a comparatively large chip surface and have a high power consumption. In order to ensure high-precision frequency fine-tuning on a particular TV channel, for instance, the invention calls for a frequency-equalizable analog circuit, e.g. an FM demodulator (23), to be equalized in an integrated circuit by a control current (Icon). The control current generated in a control loop is dependent on a reference frequency (fCH) of suitable accuracy and on a reference capacitance integrated on the chip. Following frequency selection, the analog circuit is calibrated and then the frequency fine-tuned in a measurement mode. The analog circuit subsequently operates in the normal mode. |
申请公布号 |
WO9213389(A1) |
申请公布日期 |
1992.08.06 |
申请号 |
WO1992EP00091 |
申请日期 |
1992.01.18 |
申请人 |
DEUTSCHE THOMSON-BRANDT GMBH |
发明人 |
KOBLITZ, RUDOLF;RIEGER, MARTIN;ROTH, SABINE |
分类号 |
H03J7/02;H03J3/10;H03J7/04 |
主分类号 |
H03J7/02 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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