A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor 103 generates a mechanical force that drives a component. A ripple count circuit 104 is configured to filter the drive current based on a rotational speed (ω) of the rotor 103 to generate a filtered drive current signal, and to generate a varying threshold based on the filtered drive current signal. Based on a comparison between the filtered drive current signal and the varying threshold, the ripple count circuit 104 generates a pulsed output signal indicative of the rotational speed (ω) of the rotor and a rotational position (θ) of the rotor.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor 103 generates a mechanical force that drives a component. A ripple count circuit 104 is configured to filter the drive current based on a rotational speed (ω) of the rotor 103 to generate a filtered drive current signal, and to generate a varying threshold based on the filtered drive current signal. Based on a comparison between the filtered drive current signal and the varying threshold, the ripple count circuit 104 generates a pulsed output signal indicative of the rotational speed (ω) of the rotor and a rotational position (θ) of the rotor.

An enable control circuit, which includes a counter circuit configured to count a current clock cycle and determine a clock cycle count value; a selection circuit configured to determine a clock cycle count target value according to a first setting signal; and a control circuit configured to control an ODT path to be enabled and start the counter circuit when the voltage level of an ODT pin signal is flipped over, control the ODT path to be switched from being enabled to disabled when the clock cycle count value reaches the clock cycle count target value and the voltage level of the ODT pin signal is not changed, and control the ODT path continue to be enabled when the clock cycle count value reaches the clock cycle count target value and the voltage level of the ODT pin signal flips again.

An enable control circuit, which includes a counter circuit configured to count a current clock cycle and determine a clock cycle count value; a selection circuit configured to determine a clock cycle count target value according to a first setting signal; and a control circuit configured to control an ODT path to be enabled and start the counter circuit when the voltage level of an ODT pin signal is flipped over, control the ODT path to be switched from being enabled to disabled when the clock cycle count value reaches the clock cycle count target value and the voltage level of the ODT pin signal is not changed, and control the ODT path continue to be enabled when the clock cycle count value reaches the clock cycle count target value and the voltage level of the ODT pin signal flips again.

Embodiments relate to a clock counter, a method for clock counting, and a storage apparatus. The clock counter includes a clock frequency-dividing circuit, a plurality of counting circuits, and an adding circuit. The clock frequency-dividing circuit receives a clock signal and divide a frequency of the clock signal to output a plurality of frequency-divided clock signals, sum of number of pulses of the plurality of frequency-divided clock signals being equal to number of pulses of the clock signal. The plurality of counting circuits are connected to the clock frequency-dividing circuit, each of the plurality of counting circuits being configured to respectively count pulses for each of the plurality of frequency-divided clock signals and generate an initial count value. The adding circuit is connected to the plurality of counting circuits, and adds up the initial count values of the plurality of counting circuits to generate a target count value.

A motor control system includes a DC motor and a ripple count circuit. The DC motor includes a rotor that rotates in response to a drive current. The rotation of the rotor generates a mechanical force that drives a component. The ripple count circuit includes an active filter circuit and a parasitic pulse cancellation circuit. The active filter circuit is configured to filter the drive current and to generate a pulsed signal. The parasitic pulse cancelation circuit is in signal communication with the ripple count circuit to receive the pulsed signal and generates a ripple count signal that excludes parasitic pulses included in the pulsed signal having a parasitic voltage level that exceeds a voltage level of a voltage threshold. The parasitic pulse cancelation circuit actively adjusts the voltage level of the voltage threshold based at least in part on a rotational direction of the rotor.

A motor control system includes a DC motor and a ripple count circuit. The DC motor includes a rotor that rotates in response to a drive current. The rotation of the rotor generates a mechanical force that drives a component. The ripple count circuit includes an active filter circuit and a parasitic pulse cancellation circuit. The active filter circuit is configured to filter the drive current and to generate a pulsed signal. The parasitic pulse cancelation circuit is in signal communication with the ripple count circuit to receive the pulsed signal and generates a ripple count signal that excludes parasitic pulses included in the pulsed signal having a parasitic voltage level that exceeds a voltage level of a voltage threshold. The parasitic pulse cancelation circuit actively adjusts the voltage level of the voltage threshold based at least in part on a rotational direction of the rotor.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor (103) generates a mechanical force that drives a component. A ripple count circuit (104) is configured to filter the drive current based on a rotational speed (ω) of the rotor (103) to generate a filtered drive current signal, and to generate a varying threshold based on the filtered drive current signal. Based on a comparison between the filtered drive current signal and the varying threshold, the ripple count circuit (104) generates a pulsed output signal indicative of the rotational speed (ω) of the rotor and a rotational position (θ) of the rotor.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor (103) generates a mechanical force that drives a component. A ripple count circuit (104) is configured to filter the drive current based on a rotational speed (ω) of the rotor (103) to generate a filtered drive current signal, and to generate a varying threshold based on the filtered drive current signal. Based on a comparison between the filtered drive current signal and the varying threshold, the ripple count circuit (104) generates a pulsed output signal indicative of the rotational speed (ω) of the rotor and a rotational position (θ) of the rotor.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor 103 generates a mechanical force that drives a component. A ripple count circuit 104 is configured to filter the drive current based on a rotational speed (ω) of the rotor 103 to generate a filtered drive current signal, and to generate a varying threshold based on the filtered drive current signal. Based on a comparison between the filtered drive current signal and the varying threshold, the ripple count circuit 104 generates a pulsed output signal indicative of the rotational speed (ω) of the rotor and a rotational position (θ) of the rotor.