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Patent Searching and Data


Title:
DEVICE AND METHOD FOR MEASURING CLOCK RATE
Document Type and Number:
Japanese Patent JPH04184295
Kind Code:
A
Abstract:

PURPOSE: To enable maintaining long time reliability of highly accurate measurement by a simple circuit constitution and without using a multiplier by providing the first, the second and the third counters that count the first, the second and the third gate output signals.

CONSTITUTION: A standard signal oscillator 2 is a highly stable crystal oscillator and a sub-clock oscillator 4 is a crystal oscillator that does not especially require accuracy. The first and the second counters 10 and 12 count intervals of a hand (of the watch) progressing signals with switching sub-clock signals by a switch 8 at every the hand (of the watch) progressing signal of a clock 6. On the other hand, regarding signals produced from the standard signals as standard time signals, the sub-clock signals passing through during the standard time duration, and counted by the third counter 14. Then, by comparing and adjusting counted numbers of the hand progressing signals and the sub- clock signals, 'advance' or 'delay' of the hand progressing signal of the clock 6 can be measured.


Inventors:
YAMADA JUNJI
HAMADA YOSHIAKI
YAMADA ISAO
MATSUURA MAKOTO
Application Number:
JP31509290A
Publication Date:
July 01, 1992
Filing Date:
November 20, 1990
Export Citation:
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Assignee:
FUJI ELECTRONICS CO LTD
International Classes:
G04D7/12; (IPC1-7): G04D7/12
Attorney, Agent or Firm:
Tatsuyuki Unuma (3 others)