Physical quantity detection device for converting a physical quantity into a corresponding time interval

A physical quantity detection device for detecting a physical quantity comprising:

• first pulse generating means for generating first successive pulse signals, wherein intervals between said first successive pulse signals change in response to a change in said physical quantity being detected;
• first pulse dividing means comprising:
• first counting means for counting said first successive pulse signals having a first counting pulse signal output and a first counting initiating signal input, and
• first decoding means having a first decoding signal input from said first counting pulse signal output and a first decoding pulse signal output for generating a first pulse signal when a counted value of said first counting means reaches a first predetermined value, said first decoding means further having a synchronization signal output for generating a synchronization signal, a first reset signal output for generating a first reset signal to the first counting initiating signal input for initiating said first counting means, and a second reset signal output for generating a second reset signal when a counted value of said first counting means reaches a second predetermined value;
• second pulse generating means for generating second successive pulse signals, intervals between said second successive pulse signals changing in response to said change in said physical quantity being detected, said second pulse generating means having a synchronization signal input from said first decoding means synchronization signal output for controlling said second pulse generating means by said synchronization signal so that a phase of said first successive pulse signals is synchronized with a phase of said second successive pulse signals;
• second pulse dividing means comprising:
• second counting means for counting said second successive pulse signals having a second counting pulse signal output, said second counting means further having a second initiating signal input for receiving said second reset signal from said first decoding means for initializing said second counting means, and
• second decoding means having a second decoding signal input from said second counting pulse signal output and a second decoding pulse signal output for generating a second pulse signal when a counted value of said second counting means reaches a third predetermined value;
• and
• pulse phase difference detecting means having a plurality of phase difference inputs from said first and second decoding pulse signal outputs for detecting a pulse phase difference between said first pulse signals and second pulse signals, and for outputting a resultant signal representing said physical quantity based upon said pulse phase difference;
• said first pulse generating means and said second pulse generating means each increasing a frequency of pulses generated from one of said first pulse generating means and said second pulse generating means, and each decreasing a frequency of pulses generated from another of said first pulse generating means and said second pulse generating means.

A physical quantity detection device for detecting a physical quantity comprising:

• pulse generating means for generating successive pulse signals, wherein intervals between said successive pulse signals are determined with respect to a change in said detected physical quantity, said pulse generating means for converting said physical quantity into a pulse frequency representing a time-dimension factor, and for outputting time-signals based upon said pulse frequency;
• time-pulse dividing means, for receiving said time-signals as input signals, for counting said time-signals and generating a time-pulse dividing output pulse when a counted value reaches a predetermined value, and for generating a synchronization signal when counting starts again after a counted value reaches a predetermined value;
• reference signal generating means for generating reference signals having a predetermined frequency, said reference signal generating means being cyclically in synchronization with said pulse generating means in response to said synchronization signal;
• and
• time-signal detecting means for detecting a phase-relationship between said time-pulse dividing output pulse and said reference signals, and for outputting a signal for representing said physical quantity based on said phase-relationship.

A physical quantity detection device for detecting a physical quantity of a type which can change an oscillating characteristic of an oscillating element, said device comprising:

• first oscillating means for generating a first pulse signal having a first oscillating frequency which can be changed in response to a change in said physical quantity detected;
• second oscillating means for generating a second pulse signal having a reference oscillating frequency to be compared with said first oscillating frequency of said first pulse signal;
• first counting means connected to said first oscillating means for counting a number of pulses of said first pulse signal starting from a first pulse of said first pulse signal positioned at a predetermined first counting point, and for outputting a first counting signal when said first counting means counts a first predetermined number of pulses of said first pulse signal;
• second counting means connected to said second oscillating means for counting a number of pulses of said second pulse signal starting from a first pulse of said second pulse signal positioned at a predetermined second counting point, and for outputting a second counting signal when said second counting means counts a second predetermined number of pulses of said second pulse signal;
• pulse phase difference detecting means connected to said first counting means and second counting means for detecting a phase difference between said first counting signal and said second counting signal;
• and
• detecting means, receiving an input from said phase difference detecting means, for detecting whether or not the frequency of said first pulse signal of said first oscillating means has changed, depending upon said pulse phase difference detected by said pulse phase difference detecting means;
• one of said first counting means and said second counting means outputting a synchronization signal to one of said second oscillating means and said first oscillating means respectively, after said first counting means outputs said first counting signal and said second counting means outputs said second counting signal, so that said first counting point of said first counting pulse signal is synchronized with said second counting point of said second pulse signal.

A physical quantity detection device for detecting a condition of a physical quantity comprising:

• first pulse generating means for generating successive pulse signals, an interval of said first successive pulse signals changing in response to a change in said physical quantity being detected;
• a first counter counting said successive pulse signals and generating a first pulse signal when a first counted value of said first counter reaches a first predetermined value;
• a first decoder generating a synchronization signal when said first counted value of said first counter reaches a second predetermined value;
• second pulse generating means for generating pulse signals, for stopping generation of said pulse signals after a predetermined number of pulse signals are generated, for restarting generation of said pulse signals in synchronization with one of a first level of said synchronization signal and a leading edge of said synchronization signal, and for stopping said restarting generation of said pulse signals in synchronization with one of a second level of said synchronization signal and a trailing edge of said synchronization signal;
• a second counter counting said second pulses and generating a second pulse signal when a second counted value of said second counter reaches a third predetermined value;
• and
• pulse phase difference detecting means for detecting a pulse phase difference between said first pulse signal and said second pulse signal, and for outputting a digitized signal representing said physical quantity based on said phase difference.