Systems and methods for operating a stepper motor of a pump at a desired low velocity include memory for storing information corresponding to an intake velocity profile. The intake velocity profile represents an optimized acceleration curve for operating the stepper motor over a range of motor velocities during an intake cycle. A processor of a system controller dynamically accesses the memory during the intake cycle to acquire the information representing the intake velocity profile and issues a series of pulses to the stepper motor based on this information. In response to the pulses, the stepper motor accelerates in accordance with the optimized acceleration curve represented by the intake velocity profile. The optimized acceleration curve is based on the available torque of the stepper motor across a range of motor velocities and enables the motor to operate with greater torque utilization and less margin than traditional linear acceleration profiles.

A driving device includes a stepping motor having a rotor, a coil for rotating the rotor, and a processor that drives the stepping motor. The processor generates a driving pulse for rotating the rotor of the stepping motor to a prescribed position, and outputs the driving pulse to the coil; and generates a rotation assistance pulse for rotating the rotor of the stepping motor at a prescribed speed, and outputs the rotation assistance pulse to the coil, after outputting the driving pulse but before EMF is produced by the rotation of the rotor of the stepping motor caused by the driving pulse.

A driving device includes a stepping motor having a rotor, a coil for rotating the rotor, and a processor that drives the stepping motor. The processor generates a driving pulse for rotating the rotor of the stepping motor to a prescribed position, and outputs the driving pulse to the coil; and generates a rotation assistance pulse for rotating the rotor of the stepping motor at a prescribed speed, and outputs the rotation assistance pulse to the coil, after outputting the driving pulse but before EMF is produced by the rotation of the rotor of the stepping motor caused by the driving pulse.

A refrigerator is provided. The refrigerator includes a body including a door, a door opening device including a motor, and configured to open the door through a rotation of the motor, a first sensor configured to sense an opening of the door, a second sensor configured to sense a position of the door, and a processor is included, and the processor is configured to control, based on a user command for the opening of the door being obtained, the motor to rotate at a first speed, control, based on the opening of the door being sensed by the first sensor, the motor to rotate by reducing speed in stages to a second speed which is slower than the first speed, and control, based on a position of the door being sensed in a first position by the second sensor, the motor to open the door to a second position by rotating at the second speed.

A refrigerator is provided. The refrigerator includes a body including a door, a door opening device including a motor, and configured to open the door through a rotation of the motor, a first sensor configured to sense an opening of the door, a second sensor configured to sense a position of the door, and a processor is included, and the processor is configured to control, based on a user command for the opening of the door being obtained, the motor to rotate at a first speed, control, based on the opening of the door being sensed by the first sensor, the motor to rotate by reducing speed in stages to a second speed which is slower than the first speed, and control, based on a position of the door being sensed in a first position by the second sensor, the motor to open the door to a second position by rotating at the second speed.

A refrigerator is provided. The refrigerator includes a body including a door, a door opening device including a motor, and configured to open the door through a rotation of the motor, a first sensor configured to sense an opening of the door, a second sensor configured to sense a position of the door, and a processor is included, and the processor is configured to control, based on a user command for the opening of the door being obtained, the motor to rotate at a first speed, control, based on the opening of the door being sensed by the first sensor, the motor to rotate by reducing speed in stages to a second speed which is slower than the first speed, and control, based on a position of the door being sensed in a first position by the second sensor, the motor to open the door to a second position by rotating at the second speed.

A lens control device, comprising a first stepping motor that drives a zoom lens contained in the photographing lens, a second stepping motor that drives a focus lens contained in the photographing lens, and a processor that controls the first stepping motor and the second stepping motor, whereby, within a given section in which the zoom lens and the focus lens are driven, there is a period in which at least one of the first stepping motor and the second stepping motor is driven at a constant rate, and the processor makes a time, required to move the specified section with a specified number of pulses, a specified time.

A lens control device, comprising a first stepping motor that drives a zoom lens contained in the photographing lens, a second stepping motor that drives a focus lens contained in the photographing lens, and a processor that controls the first stepping motor and the second stepping motor, whereby, within a given section in which the zoom lens and the focus lens are driven, there is a period in which at least one of the first stepping motor and the second stepping motor is driven at a constant rate, and the processor makes a time, required to move the specified section with a specified number of pulses, a specified time.

Automated speed ramp control of stepper motor acceleration and deceleration using direct memory access (DMA) and core independent peripherals (CIPs) comprises a numerically controlled oscillator (NCO) controlled through direct memory access (DMA) transfers of prescale values used in combination with a clock oscillator to generate clock pulses that are a function of the clock oscillator frequency and the prescale values. This automates changing the frequency of the NCO, thereby controlling steeper motor speed, without requiring computer processing unit (CPU) overhead. The DMA module is enabled during a first number of clock pulses for step speed acceleration, disabled during a second number of clock pulses for normal operation at full step speed, and then re-enabled during a third number of clock pulses for step speed deceleration. A table in memory may store and provide a plurality of acceleration and deceleration prescale values for DMA transfers to the NCO.

Automated speed ramp control of stepper motor acceleration and deceleration using direct memory access (DMA) and core independent peripherals (CIPs) comprises a numerically controlled oscillator (NCO) controlled through direct memory access (DMA) transfers of prescale values used in combination with a clock oscillator to generate clock pulses that are a function of the clock oscillator frequency and the prescale values. This automates changing the frequency of the NCO, thereby controlling steeper motor speed, without requiring computer processing unit (CPU) overhead. The DMA module is enabled during a first number of clock pulses for step speed acceleration, disabled during a second number of clock pulses for normal operation at full step speed, and then re-enabled during a third number of clock pulses for step speed deceleration. A table in memory may store and provide a plurality of acceleration and deceleration prescale values for DMA transfers to the NCO.