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US 8,044,617 B2Granted
Motor control circuit and operation method thereof
AssigneeLeadtrend Technology Corp.
InventorChing-Tsan Lee
Life of this patent
Estimating the term…
Abstract
A motor control circuit for controlling a motor includes a brake circuit and a control circuit. The brake circuit is for making the motor enter a braking state. The control circuit is for detecting a residual energy of the motor in the braking state. When the residual energy conforms to a predetermined criterion, the control circuit makes the motor exit the braking state.
Claims12
A motor control circuit for controlling a motor, comprising:
- a brake circuit, for making a first node and a second node of the motor form a short-circuit loop, so as to make the motor enter a braking state;
- and
- a control circuit, for detecting residual energy of the motor in the brake state, and for making the motor exit the braking state when the residual energy conforms to a predetermined criterion;
- wherein the brake circuit comprises:
- a first transistor, coupled to the first node;
- a second transistor, coupled to the second node;
- a first resistor, connected to the first transistor in series;
- and
- a second resistor, connected to the second transistor in series;
- wherein the short-circuit loop is formed when the first and second transistors become conductive, and the residual energy is determined according to at least one of a voltage drop across the first resistor and a voltage drop across the second resistor.
7 more elements
A motor control circuit for controlling a motor, comprising:
- a brake circuit, for making a first node and a second node of the motor form a short-circuit loop, so as to make the motor enter a braking state;
- and
- a control circuit, for detecting residual energy of the motor in the brake state, and for making the motor exit the braking state when the residual energy conforms to a predetermined criterion;
- wherein the control circuit comprises:
- a comparison circuit for determining whether the residual energy conforms to the predetermined criterion, and the comparison circuit determines that the residual energy conforms to the predetermined criterion when at least one of the first and second voltages is lower than a threshold voltage, and the comparison circuit comprises:
- a first comparator, for outputting a first comparison result according to the threshold voltage and the first voltage;
- a second comparator, for outputting a second comparison result according to the threshold voltage and the second voltage;
- and
- a logic unit, for determining whether the residual energy conforms to the predetermined criterion according to the first and second comparison results;
- wherein the residual energy is determined according to at least one of a first voltage at the first node and a second voltage at the second node.
7 more elements
A motor control circuit for controlling a motor, comprising:
- a brake circuit, for making a first node and a second node of the motor form a short-circuit loop, so as to make the motor enter a braking state;
- and
- a control circuit, for detecting residual energy of the motor in the brake state, and for making the motor exit the braking state when the residual energy conforms to a predetermined criterion;
- wherein the control circuit comprises:
- a comparison circuit for determining whether the residual energy conforms to the predetermined criterion, and the comparison circuit determines that the residual energy conforms to the predetermined criterion when at least one of the first and second voltages is lower than a threshold voltage, and the comparison circuit comprises:
- a reference transistor, having a first terminal coupled to a reference current, a second terminal coupled to the threshold voltage, and a control terminal coupled to the first terminal of the reference transistor;
- a first resistor;
- a second resistor;
- a first transistor, having a first terminal coupled to a logic high voltage level via the first resistor, a second terminal coupled to the first voltage, and a control terminal coupled to the control terminal of the reference transistor;
- a second transistor, having a first terminal coupled to the logic high voltage level via the second resistor, a second terminal coupled to the second voltage, and a control terminal coupled to the control terminal of the reference transistor;
- and
- a logic unit, coupled to the first and second transistors, for determining whether the residual energy conforms to the predetermined criterion according to a voltage at the first terminal of the first transistor and a voltage at the first terminal of the second transistor;
- wherein the residual energy is determined according to at least one of a first voltage at the first node and a second voltage at the second node.
10 more elements
Dependencies are inferred from the claim text.