The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 20, 2010
Filed:
Apr. 16, 2007
Noboru Takeuchi, Tenri, JP;
Takahiro Inoue, Katsuragi, JP;
Noboru Takeuchi, Tenri, JP;
Takahiro Inoue, Katsuragi, JP;
Sharp Kabushiki Kaisha, Osaka-Shi, JP;
Abstract
A comparing circuit of the present invention includes: a charging and discharging circuit to charge a capacitor with charging current and discharge the capacitor with discharging current alternately in response to a switch of an input pulse signal; a comparator circuit to compare a capacitor-voltage (Csig) of the capacitor with a first threshold voltage (Vth) and the capacitor-voltage (Csig) with a second threshold voltage (Vth), which is higher than the first threshold voltage, to generate a pulse signal responsive to a result of this comparison, and to supply an output-signal generating circuit with the pulse signal to switch a level of an output pulse-signal; and a logical operation circuit to adjust a value of the charging current and a value of the discharging current by generating a signal that is based on the pulse signal and is to adjust the value of the charging current and the value of the discharging current of the charging and discharging circuit and supplying the charging and discharging circuit with the signal thus generated. This configuration makes it possible for the comparing circuit to maintain capability of preventing errors, and at the same time, improve in capability of outputting a pulse having a same period as that of an input pulse having a short pause period.