Semiconductor integrated circuit device and oscillation frequency calibration method

Abstract

A semiconductor integrated circuit device includes a DCO and a storing unit that stores a temperature coefficient of an oscillation frequency and an absolute value of the oscillation frequency, which should be set in the DCO, corresponding to potential obtained from a voltage source that changes with a monotonic characteristic with respect to temperature.

1 . A semiconductor integrated circuit device comprising:
 an oscillator; and   an oscillation-frequency calibrator configured to transmit a control signal for controlling the oscillator, based on information for determining an oscillation frequency of the oscillator and potential information from a voltage source configured to fluctuate with a monotonic characteristic with respect to temperature.   
     
     
         2 . The semiconductor integrated circuit device of  claim 1 , wherein the oscillation-frequency calibrator is configured to generate the control signal based on the information for determining the oscillation frequency and the potential information at least two temperatures. 
     
     
         3 . The semiconductor integrated circuit device of  claim 1 , wherein the oscillation-frequency calibrator is configured to calculate a temperature coefficient and an absolute value of a desired oscillation frequency based on the information for determining the oscillation frequency and the potential information, and to generate the control signal. 
     
     
         4 . The semiconductor integrated circuit device of  claim 3 , further comprising a current source configured to generate a first control signal corresponding to the temperature coefficient, wherein
 the oscillator is an inductance-capacitance (LC) oscillator configured to operate in response to the first control signal and a second control signal corresponding to the absolute value.   
     
     
         5 . The semiconductor integrated circuit device of  claim 3 , further comprising a current source configured to generate the control signal based on the temperature coefficient and the absolute value, wherein
 the oscillator is a ring oscillator configured to operate in response to the control signal.   
     
     
         6 . The semiconductor integrated circuit device of  claim 3 , wherein the oscillation-frequency calibrator is configured to generate the control signal based on:
 a temperature coefficient representing a linear interpolant between a temperature coefficient of the oscillation frequency corresponding to a first potential from the voltage source and a temperature coefficient of the oscillation frequency corresponding to a second potential from the voltage source; and   an absolute value representing a linear interpolant between an absolute value of the oscillation frequency corresponding to the first potential from the voltage source and an absolute value of the oscillation frequency corresponding to the second potential from the voltage source.   
     
     
         7 . The semiconductor integrated circuit device of  claim 3 , wherein the oscillation-frequency calibrator is configured to linearly interpolate an Nth order temperature coefficient where N is an integer equal to or larger than 2 and an absolute value to generate the control signal. 
     
     
         8 . The semiconductor integrated circuit device of  claim 3 , wherein the oscillation-frequency calibrator comprises:
 a controller configured to control an oscillation frequency from the oscillator corresponding with a reference oscillation frequency;   a table comprising a potential from the voltage source configured to fluctuate with the monotonic characteristic associated with temperature and the oscillation frequency from the oscillator; and   an oscillation-frequency setting module configured to set a temperature frequency of an oscillation frequency corresponding to the potential from the voltage source and an absolute value of the oscillation frequency corresponding to the potential from the voltage source, by referring to the table.   
     
     
         9 . The semiconductor integrated circuit device of  claim 8 , further comprising a frequency divider connected between an input terminal of the controller and an output terminal of the oscillator. 
     
     
         10 . The semiconductor integrated circuit device of  claim 8 , further comprising a frequency divider connected between an output terminal of the controller and an input terminal of the oscillator. 
     
     
         11 . The semiconductor integrated circuit device of  claim 1 , wherein the oscillation-frequency calibrator is configured to calculate capacitance or an electric current with the oscillation frequency substantially constant with respect to temperature based on the information for determining the oscillation frequency and the potential information, and to generate the control signal. 
     
     
         12 . The semiconductor integrated circuit device of  claim 11 , further comprising
 an oscillation-frequency compensating module comprising a current source configured to generate the first control signal based on the capacitance, wherein   the oscillator is an LC oscillator configured to operate in response to the first control signal and a second control signal corresponding to the absolute value.   
     
     
         13 . The semiconductor integrated circuit device of  claim 11 , further comprising a current source configured to generate the control signal based on the capacitance, wherein
 the oscillator comprises a ring oscillator configured to operate in response to the control signal.   
     
     
         14 . The semiconductor integrated circuit device of  claim 11 , further comprising:
 an oscillation-frequency compensating module comprising a table comprising potential from a voltage source associated with capacitance or an electric current, the potential being configured to fluctuate with a monotonic characteristic with respect to temperature, and the oscillation frequency being substantially constant with respect to temperature and configured to fluctuate according to the potential at the capacitance or the electric current, wherein   the oscillation-frequency compensating module is configured to set capacitance or an electric current corresponding to the potential from the voltage source referring to the table.   
     
     
         15 . An oscillation frequency calibration method for calibrating an oscillation frequency of an oscillator, comprising:
 generating a control signal based on information for determining an oscillation frequency of the oscillator and potential information from a voltage source configured to fluctuate with a monotonic characteristic with respect to temperature; and   controlling the oscillator with the control signal.   
     
     
         16 . The oscillation frequency calibration method of  claim 15 , further comprising: calculating a temperature coefficient and an absolute value of the oscillation frequency based on the information for determining the oscillation frequency and the potential information, and generating the control signal. 
     
     
         17 . The oscillation frequency calibration method of  claim 15 , further comprising calculating capacitance at the oscillation frequency substantially constant with respect to temperature based on the information for determining the oscillation frequency and the potential information, and generating the control signal. 
     
     
         18 . The frequency oscillation calibration method of  claim 15 , further comprising calculating an electric current at the oscillation frequency substantially constant with respect to temperature based on the information for determining the oscillation frequency and the potential information, and generating the control signal. 
     
     
         19 . The frequency oscillation calibration method of  claim 15 , further comprising generating the control signal based on information for determining an oscillation frequency of the oscillator at first and second temperatures and potential information from a voltage source configured to fluctuate with a monotonic characteristic with respect to temperature at the first and second temperatures, an electric current at the oscillation frequency substantially constant with respect to temperature.