Patent ID: 7253601

Claim:
A current sensor for detecting a detection object current comprising: a current path for flowing the detection object current therethrough; a semiconductor substrate; and a Hall element disposed on a front side of the semiconductor substrate, wherein the Hall element is capable of detecting a magnetic flux generated by a magnetic field, which is caused by the detection object current when the detection object current flows through the current path, the Hall element generates a Hall voltage corresponding to the magnetic flux when a driving current flowing in a direction perpendicular to the semiconductor substrate is supplied to the Hall element, and when the magnetic flux having a component parallel to the semiconductor substrate affects the Hall element, the current path is disposed on the front side or a back side of the semiconductor substrate, and the current path is electrically isolated from the Hall element, wherein: the Hall element is a vertical type Hall element, the Hall element includes a semiconductor region, a separation wall, a first to third current supply terminals and a first and second voltage output terminals, the semiconductor region is disposed in a surface portion of the semiconductor substrate, the separation wall includes a frame, a first wall and a second wall, the frame of the separation wall surrounds the semiconductor region, the first wall and the second wall are disposed in the frame of the separation wall so that the semiconductor region is divided into a first to third element regions, each of the first and second walls has a depth, which is shallower than a depth of the semiconductor region so that the first to third element regions are electrically connected together through a part of the semiconductor region under each of the first and second walls, the first current supply terminal is disposed in the first element region, the second current supply terminal and the first and second voltage output terminals are disposed in the second element region, and the third current supply terminal is disposed in the third element region, the first and second voltage output terminals are disposed line symmetrically with a pair of the first and third current supply terminals, the second current supply terminal is disposed at a center between the first and second voltage output terminals, the Hall element includes a Hall plate as a magnetic flux detection portion, the Hall plate is provided by a part of the second element region surrounded with the first and second voltage output terminals, the driving current is supplied to the Hall plate through a pair of the first and second current supply terminals and/or a pair of the second and third current supply terminals, and the Hall voltage is outputted from the first and second voltage output terminals.