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:
Nov. 22, 2016
Filed:
Mar. 11, 2015
Renesas Electronics Corporation, Kawasaki-shi, Kanagawa, JP;
Renesas Electronics Corporation, Tokyo, JP;
Abstract
The present invention realizes a calibration operation for detecting a motor speed, without employing digital correcting by an external CPU. The calibration operation calculates a comparison reference value corresponding to aback EMF detection signal of a back EMF detector circuit when a zero current flows through a motor and when an arm is fixed. Accordingly, the back EMF detection signal of the back EMF detector circuit is set as the first value and the second value responding to the non-zero current flowing through the motor, and the semiconductor integrated circuit calculates the comparison reference value from the first value and the second value. The difference between the comparison reference value and the comparison input value as the back EMF detection signal of the back EMF detector circuit is reduced by adjusting the gain of an internal amplifier of the back EMF detector circuit by an adjustment unit.