PHYSICAL QUANTITY MEASURING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a physical quantity measuring device adopting a counter for stably counting the frequency in a short update cycle using a reference clock MCLK with a low frequency, which is formed into a small circuit scale. SOLUTION: The measuring device includes a counting/calculating part for performing counting of a counter in response to a pulse train signal Fc depending on the magnitude of a physical quantity P and calculating the physical quantity Pcalc according to the counted count value. The counting/calculating part includes: a sensor/driver means for outputting the vibration frequency depending on the magnitude of the physical quantity P as a pulse train signal Fc; an Fc counter means for starting counting in response to the pulse train signal Fc; a plurality of MCLK counter means for starting counting in response to a reference clock immediately after that every time the pulse train signal Fc is generated; and a physical quantity generating means for generating the physical quantity Pcalc obtained by dividing the value obtained by dividing the average value of added MCLK count values counted by the plurality of MCLK counter means by a natural frequency by the Fc count value counted by the Fc counter means. COPYRIGHT: (C)2004,JPO