Aimtron Technology Corp.

Faraday Technology Corporation

Hoyi Electronic Technology Co., Ltd.

Chi-Yang Chen

Guang-Nan Tzeng

Feng-Rurng Juang

Tien-Tzu Chen

Min-Fu Hsieh

San-Yueh Huang

Li-Cheng Chen

Wen-Chi Huang

An electronic rotary encoder is configured to be disposed on a vertical rotary shaft in a rotary object to obtain two encoded signals: a phase A signal and a phase B signal for calculating a rotational speed and a position. The electronic rotary encoder includes: at least one Hall element outputting Hall signals used as a square wave of the phase A signal; two capacitors, to respectively obtain a first voltage and a second voltage; two buffer gates, to respectively output waveform signals of a first X voltage and a second X voltage; two comparators outputting, a control signal through a latch; and an exclusive OR gate, where a direction signal and the control signal outputted through the latch are inputted to the exclusive OR gate, to obtain the phase B signal.

Electronic rotary encoder

A motor commutation waveform generating circuit is provided. The motor commutation waveform generating circuit includes: an edge detection circuit, configured to receive sensing signals of the motor and derive a clock signal indicating a commutation switching point of the motor; an angle cutting circuit, controlled by the clock signal to generate an angle indication pulse indicating a rotation angle of the motor; a synthetic wave generating circuit, using the angle indication pulse to sequentially change waveform voltages corresponding to required angles and output them in segments; and a signal combining circuit, controlled by the clock signal to combine waveform voltage signals generated by the synthetic wave generating circuit, thereby obtaining a plurality of synthetic waveforms provided to a drive control system of the motor for drive control after pulse width modulation.

Motor communication waveform generating circuit

A voltage regulator is connected with an input/output circuit. The voltage regulator includes a controlling circuit, a sink voltage generator and a source voltage generator. The controlling circuit generates a first reference voltage, a second reference voltage, a first power start control signal and a second power start control signal. The sink voltage generator receives the first reference voltage and the first power start control signal. The source voltage generator receives the second reference voltage and the second power start control signal. When the voltage regulator is in a normal working state, the controlling circuit inactivates the first power start control signal and the second power start control signal, the sink voltage generator generates a sink voltage according to the first reference voltage, and the source voltage generator generates a source voltage according to the second reference voltage.

Voltage regulator

A power system includes a voltage regulating system and a digital circuit. The voltage regulating system receives a power down signal. The voltage regulating system selectively generates an output voltage according to the power down signal. When the digital circuit receives the output voltage, the digital circuit is operated. When the digital circuit is not operated, the power down signal is activated. After the external voltage source is switched on and before a voltage of the external voltage source reaches a fixed voltage, the voltage regulating system ignores the power down signal and generates the output voltage. After the voltage of the external voltage source reaches the fixed voltage, the voltage regulating system generates the output voltage if the power down signal is inactivated; the voltage regulating system stops generating the output voltage if the power down signal is activated.

Anti-deadlock circuit for voltage regulator and associated power system

A voltage regulator includes an operational amplifier, a transistor, a first resistor, a second resistor, an output voltage delaying circuit and a selecting circuit. The output voltage delaying circuit receives an output voltage and generates a delayed output voltage. A first input terminal of the selecting circuit receives a reference voltage. A second input terminal of the selecting circuit receives the delayed output voltage. An output terminal of the selecting circuit generates a control voltage to a first input terminal of the operational amplifier. If the reference voltage is larger than the delayed output voltage, the selecting circuit selects the delayed output voltage as the control voltage. If the reference voltage is smaller than the delayed output voltage, the selecting circuit selects the reference voltage as the control voltage.

Voltage regulator with soft-start circuit

A voltage regulator circuit is provided, which includes a main regulator and at least one auxiliary regulator. The main regulator provides an output voltage and regulates the output voltage according to the output voltage and a reference voltage. Each auxiliary regulator is coupled to the main regulator. Each auxiliary regulator also provides the output voltage and regulates the output voltage according to the output voltage and the reference voltage. Each of the main regulator and the at least one auxiliary regulator provides a branch current of the same magnitude. An output current of the voltage regulator circuit includes the branch currents provided by the main regulator and the at least one auxiliary regulator.

Voltage regulator circuit

A voltage regulator calibration circuit including a voltage regulator and a calibration unit is provided. The voltage regulator regulates an output voltage according to a reference voltage and a feedback voltage. The feedback voltage is in direct proportion to the output voltage. The calibration unit is coupled to the voltage regulator. The calibration unit generates a control code through binary search according to the output voltage and a target voltage. The control code determines the proportion of the feedback voltage to the output voltage.

Calibration circuit for voltage regulator

A voltage regulator includes a constant voltage power circuit and an overcurrent protection circuit. The constant voltage power circuit generates an output voltage, an output current and a divided voltage. The overcurrent protection circuit includes a current sensing unit, a first mirroring unit, a voltage to current converting unit, a second mirroring unit, and a pull up unit. The current sensing unit generates a sensing current according to the output current. The first mirroring unit generates a first mirroring current. The first mirroring current is proportional to the output current. The voltage to current converting unit is used for converting the divided voltage into a first current. The second mirroring unit generates a second mirroring current. The second mirroring current is proportional to the second current. The pull up unit controls the output voltage and the output current according to the first mirroring current and the second mirroring current.

A brushless motor drive device has a signal synthesizing circuit for converting a plurality of sensing signals into a plurality of drive signals so as to determine an amplitude of each of the drive signals in accordance with a current error signal. The sensing signals are generated by a sensing circuit in response to variations in a magnetic field of a brushless multi-phase motor. The current error signal is representative of a difference between a current command signal and a motor drive current. The signal synthesizing circuit is characterized by including a calibrating circuit for adjusting the current error signal in accordance with an amplitude of any of the sensing signals. The calibrating circuit includes a differential amplifying circuit, a rectifying circuit, a filtering circuit, and a dividing circuit.

Brushless motor drive device

For applying a driving voltage to a motor, an H-bridge circuit is constructed by a first and a second linear unit and a first and a second switching unit. An error amplifier generates an error signal representative of a difference between the driving voltage detected by a voltage detecting circuit and a command voltage signal. A state control circuit synchronously controls the first and second switching units and a feedback circuit. Through the feedback circuit, the error signal is selectively applied to the first or second linear unit such that one is operated in a linear mode and the other is operated in a nonconductive mode, thereby controlling the driving voltage to become proportional to the command voltage signal. The state control circuit further controls a brake circuit for transforming the error signal into a brake signal to operate the first and second linear units simultaneously in a conductive mode.

Motor control circuit for supplying a controllable driving voltage

A motor control circuit includes a detector circuit, a comparator circuit, a sifter circuit, and a driver circuit. The detector circuit is coupled to a plurality of coils of a motor for generating a detection signal. The detection signal is in association with a terminal voltage of a selected-to-be-floated coil of the plurality of coils. Based on comparison between the detection signal and a reference voltage, the comparator circuit generates a comparison signal. The sifter circuit receives in sequence a first-time crossing and a second-time crossing from the comparison signal, and generates an indication signal in response to the second-time crossing. The driver circuit controls a commutation of the motor in response to the indication signal.

Sensorless motor control circuit without employing any mask process

A Hall sensing circuit generates a positional detection signal representative of a positional relationship between a rotor and a phase coil of a motor. A signal synthesizing circuit transforms the positional detection signal to a driving signal. Based on a comparison of the driving signal and a high-frequency reference signal, a pulse signal is generated for controlling a switching circuit to drive the motor. A current error signal is supplied through feedback to adjust a relative relationship between an amplitude of the drive signal and an amplitude of the high-frequency reference signal, thereby changing a duty ratio of the pulse signal. A duty-ratio limiting circuit is provided to limit the duty ratio of the pulse signal for ensuring a reliable rotation of the motor.

For applying a driving current to a motor, an H-bridge circuit is constructed by a first and a second switching unit and a first and a second linear unit. An error amplifier generates an error signal representative of a difference between the driving current detected by a current detecting circuit and a command current signal. A state control circuit synchronously controls the first and second switching units and a feedback circuit. Through the feedback circuit, the error signal is selectively applied to the first or second linear unit such that one is operated in a linear mode and the other is operated in a nonconductive mode, thereby controlling the driving current to become proportional to the command current signal. The state control circuit further controls a brake circuit for transforming the error signal into a brake signal to operate the first and second linear units simultaneously in a conductive mode.

Motor control circuit for supplying a controllable driving current

A Hall sensing circuit generates a positional detection signal representative of a positional relationship between a rotor and a phase coil of a motor. A signal synthesizing circuit transforms the positional detection signal to a driving signal. Based on a comparison of the driving signal and a high-frequency reference signal, a pulse signal is generated for controlling a switching circuit to dive the motor. A current error signal is supplied through feedback to adjust a relative relationship between an amplitude of the drive signal and an amplitude of the high-frequency reference signal, thereby changing a duty ratio of the pulse signal. A duty-ratio limiting circuit is provided to limit the duty ratio of the pulse signal for ensuring a reliable rotation of the motor.

A switching DC-to-DC converter includes multiple power supply channels, coupled in parallel between a DC voltage source and ground, for converting the DC voltage source into multiple DC output voltages that are separate from each other. An oscillator outputs multiple oscillating signals to render each of the multiple power supply channels make at least one switching transition differently in the time domain from others of the multiple power supply channels, thereby improving transient noise. The multiple oscillating signals include two triangular wave signals with a phase difference of 180 degrees and two pulse wave signals with a-phase difference of 180 degrees. Rising edges of the two pulse wave signals occur simultaneously with either a peak or a valley of the two triangular wave signals, respectively.

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Hsinchu, Taiwan

Chi-Yang Chen