摘要 |
A demodulator has a resistor and a capacitor that may be subject to tolerances. For tolerance correction, the FM demodulator is preferably supplied with a reference frequency, which corresponds to the nominal mid-frequency of the demodulator, which is a function of the resistor and the capacitor. Any discrepancy between the actual mid-frequency of the demodulator and its nominal mid-frequency leads to the production of a voltage that differs from a nominal voltage at the output. A detector detects this error and adjusts the values of the resistor or capacitor until the error between the nominal voltage and the voltage is zero or is a minimum. The described principle can be used, for example, in integrated mobile radio receivers.
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