Motorized window treatment

A motorized window treatment comprising:

• a covering material;
• a drive assembly configured to raise and lower the covering material;
• a motor drive unit including a motor configured to drive the drive assembly to raise and lower the covering material between a fully-open position and a fully-closed position and to any position intermediate the fully-open and fully-closed positions;
• and
• at least one battery pack configured to hold at least one battery for producing a battery voltage to power the motor drive unit;
• wherein the motor drive unit is configured to determine that the magnitude of the battery voltage is too low for continued operation and reserve enough energy in the battery to allow for at least one additional movement of the covering material to the fully-open position.

A motorized window treatment comprising:

• a covering material;
• a drive assembly configured to raise and lower the covering material;
• a motor drive unit including a motor configured to drive the drive assembly to raise and lower the covering material between a fully-open position and a fully-closed position and to any position intermediate the fully-open and fully-closed positions;
• and
• at least one battery pack configured to hold at least one battery for producing a battery voltage to power the motor drive unit;
• wherein the motor drive unit comprises a motor and a controller configured to drive the motor to adjust the position of the covering material, the motor drive unit further comprising a power supply configured to receive the battery voltage and generate a DC supply voltage having a first nominal magnitude for powering the controller, the controller configured to increase the magnitude of the DC supply voltage to a second increased magnitude greater than the first magnitude when the controller is driving the motor to raise and lower the covering material.

A motorized window treatment comprising:

• a covering material;
• a drive assembly configured to raise and lower the covering material;
• a motor drive unit including a motor configured to drive the drive assembly to raise and lower the covering material between a fully-open position and a fully-closed position and to any position intermediate the fully-open and fully-closed positions, the motor drive unit comprising a controller and a rotational position sensor to enable the motor drive unit to sense movement of an output shaft of the motor, the controller configured to determine the position of a bottom end of the covering material in response to the rotational position sensor, the motor drive unit having a memory configured to store position data related to the determined position;
• and
• at least one battery pack configured to hold at least one battery for producing a battery voltage to power the motor drive unit;
• and
• a supplemental power source for the controller, the supplemental power source configured to maintain a charged voltage for a period of time adequate to maintain the position data when the at least one battery is removed from the battery pack;
• whereby the the position data is not lost when the at least one battery is removed from the battery pack.

A motorized window treatment comprising:

• a covering material;
• a drive assembly configured to raise and lower the covering material;
• a motor drive unit including a motor configured to drive the drive assembly to raise and lower the covering material between a fully-open position and a fully-closed position and to any position intermediate the fully-open and fully-closed positions, the motor drive unit comprising a controller and a rotational position sensor to enable the motor drive unit to sense movement of an output shaft of the motor, the controller configured to determine the position of a bottom end of the covering material in response to the rotational position sensor;
• and
• wherein the covering material is engageable by a user to manually position the covering material at any position between the fully-open position and the fully-closed positions, the rotational position sensor configured to provide at least one sensor signal to the controller so that the controller can determine the position of the covering material in response to the covering material being manually adjusted.