Methods of Measuring Frequencies Including Charging Electrical Circuits

Abstract

A method of measuring a frequency of an input clock signal may include generating an output pulse responsive to an edge of the input clock signal, and charging an electrical circuit responsive to the output pulse. An analog output signal may be generated responsive to the charged electrical circuit, and the analog output signal may be converted into a digital value representing a frequency of the input clock signal. Related frequency measuring circuits and memory devices are also discussed.

1 . A method of measuring a frequency of an input clock signal, the method comprising: 
 generating an output pulse responsive to an edge of the input clock signal;    charging the electric charges responsive to the output pulse;    generating an output signal responsive to the charged electric charges; and    converting the output signal into a digital value representing a frequency of the input clock signal.    
   
   
       2 . A method according to  claim 1  further comprising: 
 converting the digital value into a frequency information signal representing a frequency of the input clock signal.    
   
   
       3 . A method according to  claim 2  wherein the frequency information signal has a first value when the frequency of the input clock signal is less than a first threshold, wherein the frequency information signal has a second value when the frequency of the input clock signal is less than a second threshold and greater than or equal to the first threshold, and wherein the frequency information signal has a third value when the frequency of the input clock signal is greater than or equal to the second threshold.  
   
   
       4 . A method according to  claim 2  wherein the digital value is a thermometer code type value, and wherein the frequency information signal is a binary code type value.  
   
   
       5 . A method according to  claim 1  wherein generating the output pulse comprises generating the output pulse responsive to rising and falling edges of the input clock signal.  
   
   
       6 . A method according to  claim 5  wherein generating the output pulse comprises delaying the clock signal by a time period to generate a delayed clock signal, and combining the clock signal and the delayed clock signal to generate the output pulse.  
   
   
       7 . A method according to  claim 6  wherein combining the clock signal and the delayed clock signal comprise performing an exclusive OR operation on the clock signal and on the delayed clock signal.  
   
   
       8 . A method of measuring a frequency of an input clock signal, the method comprising: 
 generating an output pulse responsive to an edge of the input clock signal;    charging an electrical circuit responsive to the output pulse;    generating an analog output signal responsive to the charged electrical circuit; and    converting the analog output signal into a digital value representing a frequency of the input clock signal.    
   
   
       9 . A method according to  claim 8  further comprising: 
 converting the digital value into a frequency information signal representing a frequency of the input clock signal.    
   
   
       10 . A method according to  claim 9  wherein the frequency information signal has a first value when the frequency of the input clock signal is less than a first threshold, wherein the frequency information signal has a second value when the frequency of the input clock signal is between the first threshold and a second threshold, and wherein the frequency information signal has a third value when the frequency of the input clock signal is greater than the second threshold.  
   
   
       11 . A method according to  claim 9  wherein the digital value is a thermometer code type value, and wherein the frequency information signal is a binary code type value.  
   
   
       12 . A method according to  claim 8  wherein generating the output pulse comprises generating the output pulse responsive to rising and falling edges of the input clock signal.  
   
   
       13 . A method according to  claim 12  wherein generating the output pulse comprises delaying the clock signal by a time period to generate a delayed clock signal, and combining the clock signal and the delayed clock signal to generate the output pulse.  
   
   
       14 . A method according to  claim 13  wherein combining the clock signal and the delayed clock signal comprise performing an exclusive OR operation on the clock signal and on the delayed clock signal.  
   
   
       15 . A method according to  claim 8  wherein the electrical circuit comprises a capacitor.  
   
   
       16 . A method according to  claim 15  wherein charging the electrical circuit comprises pumping charge to the capacitor responsive to the output pulse.