Fan motor driving apparatus and method, cooling system including the same, and electronic equipment

摘要

A motor driving apparatus comprises an H bridge circuit having outputs coupled with a motor coil of a single-phase motor, a hall comparator configured to generate a hall detection signal indicating a position of a rotor of the motor, an electric angle generator configured to generate a pulse signal indicating that the motor rotates by a predetermined electric angle, a current monitoring circuit configured to asserts a zero current detection signal upon detecting a reversed direction of a coil current; a transition trigger circuit configured to assert a transition pulse when a count value of the first counter matches an lead angle set value; a logic circuit configured to transition the H bridge circuit according to a predetermined sequence of states; and a lead angle controller configured to adjust the lead angle set value based on a timing of assertion of the zero current detection signal.

主权项

1. A motor driving apparatus for driving a single-phase motor, comprising:
an H bridge circuit configured to receive a power supply voltage and a ground voltage, and having a first output and a second output which are coupled with a motor coil of the single-phase motor; a hall comparator configured to compare a pair of hall signals generated by a hall element and generate a hall detection signal indicating a position of a rotor of the single-phase motor; a speed detection circuit configured to receive the hall detection signal and generate a speed detection signal having a period depending on the rotational speed of the single-phase motor; an electric angle generator configured to generate a pulse signal which has a frequency of a unit fraction of an integer part of the period of the speed detection signal and indicates that the single-phase motor rotates by a predetermined electric angle; a current monitoring circuit configured to asserts a zero current detection signal when an reversion of direction of a coil current flowing into the motor coil is detected; a transition trigger circuit including a first counter reset which is reset at every edge of the hall detection signal and performing a count operation using the pulse signal as a clock, and configured to assert a transition pulse when a count value of the first counter matches an lead angle set value; a logic circuit configured to transition the H bridge circuit among a plurality of states according to a predetermined sequence, using at least the transition pulse as a trigger; and a lead angle controller configured to adjust the lead angle set value based on a timing of assertion of the zero current detection signal.