Patent ID: 7366599
Filing Date: 2008-04-29
Classification: B62D

Abstract:
1. An electric power steering apparatus that performs steering assist by transmitting a driving force produced by an electric motor to a steering mechanism, comprising: a current detection circuit for detecting a current flowing through the electric motor to output a motor current detection signal, the current detection circuit including a variable gain amplification circuit whose gain can be changed, the current detection circuit outputting the motor current detection signal amplified by the variable gain amplification circuit; and a microcomputer, having an analog-to-digital conversion port to which the motor current detection signal outputted by the current detection circuit is inputted and also having a gain change section for changing the gain of the variable gain amplification circuit, for controlling the electric motor on the basis of the received motor current detection signal through the analog-to-digital conversion port, wherein the gain change section determines the gain of the variable gain amplification circuit such that the smaller a motor current represented by the motor current detection signal received from the analog-to-digital conversion port is, the larger the gain is.