Abstract: A motor current controlling circuit having a voltage detection mechanism is provided. A first terminal of a first low-side transistor is connected to a second terminal of a first high-side transistor. A node between the first terminal of the first low-side transistor and the second terminal of the first high-side transistor is connected to a first terminal of a motor. A first terminal of a second low-side transistor is connected to a second terminal of a second high-side transistor. A zero current detector circuit detects a voltage of the node and determines whether or not a current flowing through the motor is equal to a zero value to output a zero current detected signal according to the detected voltage. A controller circuit controls a driver circuit to turn on or off the high-side transistors and the low-side transistors according to the zero current detected signal.

Abstract: A signal gain determination circuit including a digital comparator, a digital controller and an arithmetic module, and a signal gain determination method are provided. A sensing integration circuit generates a first count during a first integration time according to a first sensing signal. The digital comparator compares the first count and a predetermined count to generate a comparison result. The digital controller generates a control signal for indicating a signal gain to a signal amplifier of the sensing integration circuit according to the comparison result. The signal amplifier adjusts the first sensing signal according to the signal gain to generate a second sensing signal, so that the sensing integration circuit generates a second count corresponding to the second sensing signal during a second integration time. The arithmetic module generates an output count corresponding to the first sensing signal according to the second count and the signal gain.

Abstract: A motor protecting circuit is provided. A first terminal of each of high-side transistors is coupled to a power supply voltage. A second terminal of each of low-side transistors is grounded. Second terminals of the high-side transistors are respectively connected to first terminals of the low-side transistors. An overvoltage detector circuit is coupled to the power supply voltage of an output circuit. When the overvoltage detector circuit determines that the power supply voltage of the output circuit is higher than a voltage threshold, the overvoltage detector circuit outputs an overvoltage detected signal to a controller circuit. According to the overvoltage detected signal, the controller circuit controls a driver circuit to turn on at least one of the high-side transistors and at least one of the low-side transistors at the same time.

Abstract: A power converter with a negative current detection mechanism is provided. A negative current detecting circuit includes a first operational amplifier, a first transistor and a second transistor. A non-inverting input terminal of the first operational amplifier is connected to a second terminal of a sense resistor. An inverting input terminal of the first operational amplifier is connected to a first terminal of a first capacitor. Control terminals of the first and second transistors are connected to an output terminal of the first operational amplifier. A first terminal of the first transistor is connected to the second terminal of the sense resistor. A second terminal of the first transistor is grounded. A first terminal of the second transistor is connected to the inverting input terminal of the first operational amplifier and the first terminal of the first transistor. A second terminal of the second transistor is grounded.

Abstract: A circuit measuring device and a method thereof are provided. A voltage source supplies a common voltage such that a calibration current having a preset current value flows from a current-voltage converter to a final test machine. The current-voltage converter converts the calibration current into a calibration voltage. At this time, a voltage sensing component senses a voltage between an input terminal and an output terminal of the current-voltage converter to output sensed calibration data. The current-voltage converter converts a tested current outputted by a tested circuit into a tested voltage. At this time, the voltage sensing component senses the voltage between the input terminal and the output terminal of the current-voltage converter to output actual sensed data. When the final test machine determines that a difference between the sensed calibration data and the actual sensed data is larger than a threshold, the tested circuit is adjusted.

Abstract: An electromagnetic interference reducing circuit is provided. A first random number generator generates a plurality of first random number signals each having a plurality of triangular waves. Each of the triangular waves has a plurality of steps. The first random number generator generates a plurality of first random numbers and modulates each of the first random number signals according to the first random numbers. The first random number generator repeatedly counts, repeatedly removes, or does not count time of the steps of each of the triangular waves of each of the first random number signals according to one of the first random numbers. A first oscillator generates a first oscillating signal. A motor controller circuit controls a plurality of switch components of a motor respectively according to the first random number signals based on the first oscillating signal.

Abstract: A three-phase motor driving circuit and a three-phase motor driving method are provided. The three-phase motor driving circuit includes an inverter circuit, a control circuit, a turn-off module, a turn-off confirmation module, and a turn-on logic unit. The inverter circuit includes a plurality of phase circuits, each including an upper bridge switch and a lower bridge switch. The control circuit operates in a feedback mode to output a feedback start signal. The turn-off module includes a feedback detection unit, a voltage adjusting unit, and a turn-off logic unit. The feedback detection unit detects an output current of a designated phase circuit, and if the output current flows out, a voltage regulation signal is output until the output current is 0, and a lower bridge turn-off signal is output. The voltage adjusting unit adjusts the voltage of the output node to be close to a predetermined voltage.

Abstract: A counter is provided. A charge distributing circuit includes a first switch, a second switch, a third switch, a fourth switch, a third capacitor and a fourth capacitor. A first terminal of the first switch and a first terminal of the third switch are connected to a first input terminal of an operational amplifier. A second terminal of the first switch is connected to a first terminal of the third capacitor and a first terminal of the fourth switch. A second terminal of the third switch is connected to a first terminal of the fourth capacitor and a first terminal of the second switch. A second terminal of the third capacitor and a second terminal of the fourth capacitor are grounded. A second terminal of the second switch and a second terminal of the fourth switch are coupled to a reference voltage.

Abstract: A transient response improving system and method with a prediction mechanism of an error amplified signal are provided. A current sensor circuit senses a current flowing through a first resistor connected between an adapter and an electronic device. When the current is larger than a current threshold, a predicting circuit calculates a target voltage level based on a common voltage and a voltage of the battery and instantly pulls up or down a voltage level of the error amplified signal to the target voltage level. A comparator compares the error amplified signal with a ramp signal to output a comparison signal. A controller circuit controls a driver circuit to switch a high-side switch and a low-side switch according to the comparison signal.

Abstract: A dual-slope optical sensor is provided. Two terminals of a first charging switch are respectively connected to an optoelectronic component and a first terminal of a capacitor. Two terminals of a second charging switch are respectively connected to a second terminal of the capacitor and grounded. First terminals of third charging and discharging switches are respectively connected to the first and second terminals of the capacitor. First terminals of fourth charging and discharging switches are respectively coupled to first and second reference voltages. Two terminals of a first discharging switch are respectively connected to the optoelectronic component and the second terminal of the capacitor. A first input terminal of a comparator is connected to second terminals of the third charging switch and the fourth discharging switch. A second input terminal of the comparator is connected to second terminals of the fourth charging switch and the third discharging switch.

Abstract: A method of adjusting brightness of a display device is provided. The method includes steps of: generating a synchronization signal having a plurality of periods each of which is a frame time; determining bit values of dithering data according to target brightness data; and determining how many pulse waves in the pulse wave width modulation signal need to be modulated within the frame time according to the bit values of the dithering data, and accordingly modulating widths of the pulse waves of the pulse wave width modulation signal.

Abstract: A driver circuit of a capacitive speaker is provided. Positive and negative power terminals of a first output stage circuit are respectively coupled to a first power source and a second power source. The first output stage circuit outputs a first voltage signal to a first terminal of a capacitive load of the capacitive speaker according to a first audio input signal, a voltage of the first power source and a voltage of the second power source. Positive and negative power terminals of a second output stage circuit are respectively coupled to the second power source and a third power source. The second output stage circuit outputs a second voltage signal to a second terminal of the capacitive load of the capacitive speaker according to a second audio input signal, a voltage of the second power source and a voltage of the third power source.

Abstract: A method of stabilizing data of digital signals is provided. The method includes steps of: (a) determining whether or not next input data is larger than previous output data, if yes, adding a base value to a trend value and then performing step(c), if no, performing step(b); (b) determining whether or not the next input data is smaller than the previous output data, if yes, subtracting the base value from the trend value and performing step(c), if no, performing step(c); (c) determining whether or not the trend value is larger than a positive threshold, if yes, subtracting a trend correction coefficient from the previous output data, if no, performing step(d); and (d) determining whether or not the trend value is smaller than a negative threshold, if yes, adding the trend correction coefficient to the previous output data; if no, outputting the previous output data.

Abstract: A system of driving and controlling a motor is provided. A main controller adjusts frequencies of all or some of pulse waves of an initial pulse width modulation signal to output a pulse width modulation signal according to instruction information. The adjusted frequency of each of the pulse waves is equal to a first preset frequency or a second preset frequency. When a motor driver drives the motor to stably rotate, the motor driver decodes each of the pulse waves having the first preset frequency into a first message and decodes each of the pulse waves having the second preset frequency into a second message. The motor driver arranges and combines all of the first messages and the second messages that are decoded from the pulse waves to obtain the instruction information. The motor driver executes an operation instructed by the instruction information.

Abstract: A power converter including switch components having different safe operating areas is provided. A first terminal of a first high-side switch is coupled to a common voltage. A first terminal of a first low-side switch is connected to a second terminal of the first high-side switch. A second terminal of the first low-side switch is grounded. A first terminal of a second low-side switch is connected to a node between the second terminal of the first high-side switch and the first terminal of the first low-side switch. A second terminal of the second low-side switch is grounded. A safe operating area of the second low-side switch is larger than a safe operating area of the first low-side switch. After the first low-side switch is turned off, the second low-side switch is turned off Before the first low-side switch is turned on, the second low-side switch is turned on.

Abstract: A motor output stabilizing circuit and a method are provided. A sensor senses a positive voltage and a negative voltage that are generated with a change in magnetic field strength of a motor of which a rotor is rotating. A comparator compares the positive voltage with the negative voltage to output a Hall signal. An average counter records a first time during which the positive voltage is higher than the negative voltage and a second time during which the negative voltage is higher than the positive voltage, according to the Hall signal. The average counter then averages the first time and the second time to output an averaged time signal. A motor controller circuit controls a motor driver circuit to drive the motor according to the averaged time signal, such that the motor outputs a constant current.

Abstract: A power converter, a synchronous power converter system and a method of determining switching frequency are provided. A processor is configured to output a synchronous clock signal corresponding to a first switching frequency. A plurality of first-stage power converters are coupled to the processor, and configured to generate a plurality of first output voltages corresponding to the first switching frequency according to the synchronous clock signal and a system voltage. At least one second-stage power converter is coupled to the processor and one of the plurality of first-stage power converters, and configured to generate a second output voltage corresponding to a second switching frequency according to the synchronous clock signal, a multiplied frequency control signal and one of the plurality of first output voltages. The second switching frequency is a multiple of the first switching frequency.

Abstract: A power converter with an automatic balance mechanism of a flying capacitor is provided. The flying capacitor and a first terminal of an output inductor are connected to a switch circuit. Two terminals of an output capacitor are respectively connected to a second terminal of the output inductor and grounded. Two input terminals of an error amplifier are respectively connected to a node between the output capacitor and the output inductor, and coupled to a reference voltage. The error amplifier outputs an error amplified signal according to a voltage of the node and the reference voltage. A comparator circuit receives a ramp signal. A slope of the ramp signal is proportional to a voltage of the flying capacitor. The comparator circuit compares the ramp signal with the error amplified signal to output a comparison signal. The driving circuit drives the switch circuit according to the comparison signal.

Abstract: A motor driving circuit and a motor driving method are provided. The motor driving circuit is used to drive the motor and includes an inverter circuit, a control circuit, a current-limiting circuit, a start circuit and a transient circuit. The control circuit controls the inverter circuit to drive the motor with a motor control current according to a set current limit value indicated by a current-limiting signal, and outputs a steady state ready signal in response to the motor reaching a steady state. The current-limiting circuit generates the current-limiting signal according to a start state signal, or generates the current-limiting signal according to a transient signal. The start circuit outputs the start state signal when the motor starts. The transient circuit detects whether the motor is in a transient state, and outputs the transient signal in response to the motor being in a transient state.

Abstract: An inductor current detecting circuit is provided. A current supplying circuit supplies a first current signal to an energy storage circuit having a zero voltage during a high-side conduction time, and a second current signal to the energy storage circuit having the zero voltage during a low-side conduction time. A voltage comparator circuit subtracts a valley voltage of a low-side switch from a peak voltage of a high-side switch to obtain a reference voltage, and outputs a comparison signal according to a voltage of the energy storage circuit and a reference voltage. A current modulation controller circuit modulates currents of the first and second current signals according to the comparison signal. A synthesizing circuit synthesizes the first and the second current signals, each of which charges the voltage of the energy storage circuit to be equal to the reference voltage from zero, to obtain an inductor current signal.