Frequency-to-voltage converting apparatus

A frequency-to-voltage converting apparatus comprising:

• counting means for counting each time period of an input pulse signal applied thereto and for generating a count signal representative thereof;
• clock signal generating means for generating a clock signal having a set time period corresponding to a clamping frequency;
• comparing means connected to said counting means for receiving said count signal and comparing said time period of said input pulse signal counted by said counting means with said set time period, every time period of said input pulse signal, and outputting a comparison result;
• selecting/outputting means connected to said clock signal generating means and said comparing means to respectively receive said clock signal and said comparison result for receiving said input pulse signal and selecting, based on said comparison result of said comparing means, one of said input pulse signal and said clock signal, and outputting said selected signal;
• and
• voltage converting means for generating a converted output signal having a voltage corresponding to a frequency of said pulse signal output from said selecting/outputting means.

A frequency-to-voltage converting apparatus comprising:

• edge detecting means for detecting an edge of an input pulse signal applied thereto and outputting an edge detection signal representative thereof;
• counting means for counting a time period of said input pulse signal using said edge detection signal output from said edge detecting means and for generating data indicative of said time period;
• setting data outputting means for outputting clamping frequency data corresponding to a set time period of a predetermined clamping frequency;
• comparing means, connected to said counting means to receive said count data and to said setting data outputting means to receive said clamping frequency data, for comparing data indicative of said time period of said input pulse signal with said clamping frequency data, to produce a comparison result;
• clock signal generating means for generating a clock signal having said set time period;
• selecting/outputting means connected to said comparing means to receive said comparison result and to said clock signal generating means to receive said clock signal, for receiving said input pulse signal and for selecting, based on said comparison result of said comparing means, one of said input pulse signal and said clock signal, and outputting an output pulse signal representative thereof;
• and
• voltage converting means connected to said selecting/outputting means for generating a converted output signal having a voltage corresponding to a frequency of said pulse signal output from said selecting/outputting means.

A frequency-to-voltage converting apparatus comprising:

• time period measuring means for measuring a time period of an input pulse signal applied thereto and outputting time period data representative of said time period;
• time period data converting means connected to said time period measuring means to receive said time period data for converting said time period data to clamped data indicative of a predetermined clamping frequency;
• pulse signal generating means connected to said time period data converting means to receive said clamped data for generating an output pulse signal having a time period and a constant pulse width corresponding to said clamped data;
• and
• voltage converting means connected to said pulse signal generating means for outputting a converted output signal having a voltage proportional to a duty ratio of said output pulse signal.

A frequency-to-voltage converting apparatus comprising:

• edge detecting means for detecting an edge of an input pulse signal applied thereto and outputting an edge detection signal representative of said edge;
• counting means, connected to said edge detecting means to receive said edge detection signal, for counting a number of clock signals between successive edge detection signals corresponding to a time period of said input pulse signal;
• setting data outputting means for outputting clamping frequency data corresponding to a set time period corresponding to a clamping frequency;
• comparing means, connected to said counting means to receive said count of said number of clock signals and said setting data outputting means to receive said clamping frequency data, for comparing data indicative of said time period of said input pulse signal with said clamping frequency data, to produce a comparison result;
• clock signal generating means for generating a clock signal having said set time period;
• selecting/outputting means, connected to said edge detecting means, said comparing means and said clock signal generating means, and to which said edge detection signal from said edge detection means and said clock signal from said clock signal generating means are input as input signals, and to which said comparison result from said comparing means is input as a selection signal, for selecting, based on said comparison result, one of said clock signal and said input pulse signal as an output pulse signal;
• and
• voltage converting means, connected to said selecting/outputting means to receive said output pulse signal, for generating a converted output signal having a voltage indicative of a frequency of said pulse signal.

A frequency-to-voltage conversion apparatus comprising:

• edge detecting means for detecting an edge of an input pulse signal a thereto and outputting an edge detection signal representative of said edge;
• counting means, connected to said edge detecting means to receive said edge detection signal, for counting a number of clock signals between successive edge detection signals corresponding to a time period of said input pulse signal and outputting time period data representative thereof;
• period data converting means, connected to said counting means to receive said time period data, for converting said time period data to converted time period data;
• pulse signal generating means, connected to said period data converting means to receive said converted time period data, for generating an output pulse signal having a time period and constant pulse width corresponding to said converted time period data;
• and
• voltage converting means, connected to said pulse signal generating means to receive said output pulse signal, for outputting a signal having a voltage which is proportional to a duty factor of said output pulse signal.

A frequency-to-voltage converting apparatus comprising:

• a clock signal generator to output a clock signal having a clamping frequency;
• a comparator to generate a comparison signal representative of whether or not a frequency of an input pulse signal applied thereto reaches said clamping frequency;
• a frequency-to-voltage converter to generate an output signal having a voltage corresponding to a frequency of an input conversion signal thereto;
• and
• a switch, connected to said clock signal generator to receive said clock signal and controlled by said comparison signal, to receive said input pulse signal and provide as said input conversion signal, said input pulse signal when said frequency of said input pulse signal is less than said clamping frequency, and said clock signal when said frequency of said input pulse signal is greater than said clamping frequency.

A frequency-to-voltage converting apparatus comprising:

• a counter to count each time period of an input pulse signal applied thereto as count data;
• a clock signal generator to generate a clock signal having a set time period corresponding to a clamping frequency;
• a comparator connected to said counter to receive said count data and to compare said time period of said input pulse signal counted by said counter as represented by said count data with said set time period, every time period of said input pulse signal, and to output a comparison result indicative thereof;
• a switch, connected to said comparator to receive said comparison result and to said clock signal generator to receive said clock signal, to receive said input pulse signal and select, based on said comparison result of said comparator, one of said input pulse signal and said clock signal as an output pulse signal;
• and
• a frequency-to-voltage converter to generate a converted output signal having a voltage representative of a frequency of said pulse signal.

A frequency-to-voltage converting apparatus comprising:

• an edge detector to detect an edge of an input pulse signal applied thereto and output an edge detection signal representative thereof;
• a counter connected to said edge detector to receive said edge detection signal to count a time period of said input pulse signal using said edge detection signal;
• a memory to output clamping frequency data indicative of said time period of a predetermined clamping frequency;
• a comparator connected to said counter to receive said counted input pulse signal time period and to said memory to receive said clamping frequency data indicative of said time period of a predetermined clamping frequency to compare said data indicative of said time period of said input pulse signal with said clamping frequency data, to produce a comparison result;
• a clock generator to generate a clock signal having said set time period;
• a switch connected to said clock generator to receive said clock signal and to said comparator to receive said comparison result to receive said input pulse signal and select, based on said comparison result of said comparator, one of said input pulse signal and said clock signal as an output pulse signal;
• and
• a frequency-to-voltage converter connected to said switch to receive said output pulse signal and to generate a converted output signal having a voltage corresponding to a frequency of said output pulse signal.