Electronic timepiece and motor control circuit

An electronic timepiece comprising:

• a motor having a coil and a rotor;
• a driver that has a terminal through which drive current is supplied to the coil, and which is controlled to an on state supplying the drive current to the coil, and an off state not supplying the drive current;
• a current detector configured to detect a current value flowing through the coil;
• a controller configured to control the driver to the on state or the off state according to the current value detected by the current detector;
• a polarity changer configured to determine driving one step of the motor ended and change the polarity of the drive current when an on time, which is a continuous time of the on state of the driver, or an off time, which is a continuous time of the off state of the driver, is detected to meet a specific condition;
• a remaining drive step count detector configured to detect whether or not a remaining drive step count, which indicates a remaining number of drive steps until driving the motor ends and is counted down 1 each time the polarity of the drive current changes, is less than or equal to a remaining count evaluation number;
• and
• a drive period adjuster configured to adjust the polarity changer to change the polarity of the drive current after a first specific time passes from detecting that the specific condition was met if the remaining drive step count is greater than the remaining count evaluation number, and if the remaining drive step count is less than or equal to the remaining count evaluation number, change the polarity of the drive current after a second specific time that is longer than the first specific time passes from detecting that the specific condition was met.

A motor control circuit comprising:

• a driver that has a terminal through which drive current is supplied to the coil of a motor, and which is controlled to an on state supplying the drive current to the coil, and an off state not supplying the drive current;
• a current detector configured to detect a current value flowing through the coil;
• a controller configured to control the driver to the on state or the off state according to the current value detected by the current detector;
• a polarity changer configured to determine driving one step of the motor ended and change the polarity of the drive current when an on time, which is a continuous time of the on state of the driver, or an off time, which is a continuous time of the off state of the driver, is detected to meet a specific condition;
• a remaining drive step count detector configured to detect whether or not a remaining drive step count, which indicates a remaining number of drive steps until driving the motor ends and is counted down 1 each time the polarity of the drive current changes, is less than or equal to a remaining count evaluation number;
• and
• a drive period adjuster configured to adjust the polarity changer to change the polarity of the drive current after a first specific time passes from detecting that the specific condition was met if the remaining drive step count is greater than the remaining count evaluation number, and if the remaining drive step count is less than or equal to the remaining count evaluation number, change the polarity of the drive current after a second specific time that is longer than the first specific time passes from detecting that the specific condition was met.