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:
Dec. 12, 2000
Filed:
Jun. 12, 1998
Manabu Matsumoto, Handa, JP;
Ichiro Yoshida, Takahama, JP;
Denso Corporation, Kariya, JP;
Abstract
A method and apparatus for enabling a processor to execute processing routine even if a power-source voltage drop occurs during processing. When an ignition key switch 102 is closed, voltage VB is supplied from a vehicle-mounted battery B1 to a comparator AMP of a CPU 108 and to a power-source stabilizer circuit 201 of a regulator 200. Also, capacitors C1 and C2 are charged with a load from the vehicle-mounted battery B1. Even if the power-source line is momentarily interrupted while in this state, the capacitor C1 has already been charged, and so the transition of the drop in voltage VB is gradual compared with a case wherein the capacitor C1 is absent. Additionally, because the capacitor C2 has already been charged, voltage VCC supplied to the CPU 108 from the regulator 200 is held at a fixed value for a certain interval. Because of this, the drop in voltage VCC is delayed and the power source is switched from the vehicle-mounted battery B1 to a battery B2, thereby allowing the CPU 108 to continue to perform uninterrupted data processing.