Frequency change measuring device

A frequency change measuring device comprising:

• at least one frequency divider for frequency dividing a measuring signal having a frequency that is varied by a change in physical quantity to produce frequency-divided signals;
• at least one first counter for counting the frequency-divided signals to calculate frequency-division numbers;
• at least one frequency division numbers transmitter for transmitting the frequency division numbers in synchronism with the frequency-divided signals;
• a frequency division numbers receiver for receiving the frequency division numbers transmitted from the frequency division numbers transmitter to output the frequency division numbers;
• a second counter for counting an output of a reference clock generator which generates reference clock pulses;
• a latch unit for latching a count of the second counter on the basis of signals synchronous with the frequency division numbers from the frequency division numbers receiver;
• and
• an operations unit for determining a change in the frequency of the measuring signal on the basis of the count latched by the latch unit and the frequency division numbers, wherein the operations unit:
• calculates a difference between the count latched by the latch unit at a first time and the count latched by the latch unit at a second time, and
• determines the change in frequency of the measuring signal based on the difference between the counts latched by the latch unit at the first and second times and a difference between the frequency division numbers at the first and second times.