Abstract: Disclosed is a three-axis Hall angle sensor with an accuracy of 0.3°. The sensor is mainly designed by means of finite element software and COMSOL Multiphysics. The present specification will be mainly performed in three steps. In the first step, a cross-shape horizontal Hall element for measuring the magnetic field in the vertical direction, that is, the direction z, is studied. The second section mainly studies a three-contact four-Hall vertical element for measuring the magnetic field in the directions x, y. The third part is to design the angle sensor. Compared with the horizontal Hall element, the vertical Hall element has a relatively large offset, therefore, four vertical Hall elements are used to measure the magnetic field in the horizontal direction, and two complementary vertical structures are used to eliminate the error when the magnetic field in the same horizontal direction is measured.

Abstract: A DC-DC converter circuit with selectable working modes is disclosed. Compared with the traditional chip that works in one mode, the DC-DC converter with selectable working modes adds only a mode selection circuit, so that the chip can work in voltage control mode or current control mode. On the one hand, the applications of the chip are more extensive, and on the other hand, when the applications are different, the cost of developing a DC-DC converter with selectable working mode is greatly reduced compared with the traditional DC-DC converter.

Abstract: A DC-DC converter circuit with selectable working modes is disclosed. Compared with the traditional chip that works in one mode, the DC-DC converter with selectable working modes adds only a mode selection circuit, so that the chip can work in voltage control mode or current control mode. On the one hand, the applications of the chip are more extensive, and on the other hand, when the applications are different, the cost of developing a DC-DC converter with selectable working mode is greatly reduced compared with the traditional DC-DC converter.