Method for calibrating frequency of gm-C filter and devices using the method
AssigneeSamsung Electronics Co., Ltd.
InventorYun-Cheol Han
Life of this patent
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Abstract
A method of calibrating the frequency of a gm-C filter is provided. The method includes generating, by a frequency calibration circuit, a calibration code capable of tuning a cut-off frequency of the gm-C filter according to a frequency of an oscillation signal that is output from a gm-C oscillator and indicates a process distribution and a reference code, determining, by the frequency calibration circuit, whether the calibration code exists within a range of a reference code, and outputting, by the frequency calibration circuit, the calibration code to the gm-C filter or generating a variable current to simultaneously tune transconductance of the gm-C oscillator and transconductance of the gm-C filter, according to a result of the determination.
Claims14
A method of calibrating a frequency of a gm-C filter, the method comprising:
- generating, by a frequency calibration circuit, a calibration code for tuning a cut-off frequency of the gm-C filter according to a received reference code and a frequency of an oscillation signal that is output from a gm-C oscillator;
- determining, by the frequency calibration circuit, whether the calibration code exists within a range of the received reference code;
- and
- outputting, by the frequency calibration circuit, the calibration code to the gm-C filter when the calibration code is within the range of the reference code, and outputting a current control code when the calibration code is outside the range of the reference code to generate a variable current to tune a transconductance of the gm-C oscillator and a transconductance of the gm-C filter, wherein tuning the transconductance of the gm-C oscillator changes the frequency of the oscillation signal and tuning the transconductance of the gm-C filter adjusts a cut-off frequency of the gm-C filter.
A frequency calibration device adapted to calibrate a frequency of a gm-C filter, the frequency calibration device comprising:
- a gm-C oscillator configured to generate an oscillation signal having a frequency that varies, and
- a frequency calibration circuit configured to generate a calibration code to tune a cut-off frequency of the gm-C filter, according to the frequency of the oscillation signal and a received reference code, wherein the frequency calibration circuit determines whether the calibration code exists within the range of the received reference code and outputs the calibration code to the gm-C filter when the calibration code is within the range and generates a current control code when the calibration code is outside the range to generate a variable current to tune a transconductance of the gm-C oscillator and a transconductance of the gm-C filter, wherein tuning the transconductance of the gm-C oscillator changes the frequency of the oscillation signal and tuning the transconductance of the gm-C filter adjusts the cut-off frequency of the gm-C filter.
A data processing system, comprising:
- a non-transitory recording medium configured to store data;
- a pickup unit configured to pick up the data stored in the recording medium;
- a voltage control amplifier configured to amplify a signal output by the pickup unit;
- a gm-C filter configured to perform filtering on an amplified signal obtained by the voltage control amplifier;
- and
- a frequency calibration device configured to generate a calibration code or a reference current adapted to tune a cut-off frequency of the gm-C filter, wherein the frequency calibration device, includes:
- a gm-C oscillator configured to generate an oscillation signal having a frequency that varie;
- and
- a frequency calibration circuit configured to generate the calibration code according to the frequency of the oscillation signal and a received reference code, wherein the frequency calibration circuit determines whether the calibration code exists within the range of the received reference code and outputs the calibration code to the gm-C filter when the calibration code is within the range and generates a current control code when the calibration code is outside the range to generate a variable current to tune a transconductance of the gm-C oscillator and a transconductance of the gm-C filter, wherein tuning the transconductance of the gm-C oscillator changes the frequency of the oscillation signal and tuning the transconductance of the gm-C filter adjusts the cut-off frequency of the gm-C filter.
Dependencies are inferred from the claim text.