Abstract: An electronic device includes first and second device bodies, a pivot base, a pivot sleeve and an optical sensing device disposed on the pivot base. The pivot base is pivoted to the first and second device bodies, such that the second device body is pivotable via the pivot base. The pivot sleeve is sleeved at a pivotal connection position between the pivot base and the second device body to pivot together with the second device body and is formed with a color variation pattern or a reflective structure. Light emitted by the optical sensing device is incident upon the color variation pattern or a reflective structure and reflected to the optical sensing device when the pivot sleeve pivots, such that the optical sensing device generates an optical sensing signal corresponding to a pivot angle of the pivot sleeve according to a light reflection amount received by the optical sensing device.

Abstract: An audio amplifier includes a loop filter, at least one high pass filter (HPF) circuit, a pulse width modulation (PWM) generator, and a power stage. The loop filter is arranged to receive an audio signal and a feedback signal, and includes a first amplifier and a second amplifier, wherein the first amplifier has a first output node, and is arranged to process the audio signal and the feedback signal; the second amplifier has a first input node, and is arranged to receive a first amplifier input and a second amplifier input; and the first amplifier input is obtained from a signal path coupled between the first output node and the first input node. The at least one HPF circuit is coupled between the first amplifier and the second amplifier, and is arranged generate and output the second amplifier input according to an amplifier output of the first amplifier.

Abstract: A Class-D audio amplifier includes a triangular wave generator, a wave reshaping device and a pulse-width modulator. The triangular wave generator generates a first triangular wave. The wave reshaping device generates a second triangular wave by reshaping the first triangular wave. The pulse-width modulator modulates a pair of differential audio input waves with the second triangular wave instead of the first triangular wave to reduce a switching loss of the Class-D audio amplifier.

Abstract: An audio amplifier chip includes an audio amplifier, a current providing circuit, a detection circuit, and a control circuit. The audio amplifier is arranged to drive a speaker, wherein the audio amplifier has multiple differential input terminals, and a direct current (DC) blocking capacitor is coupled to one of the multiple differential input terminals. The current providing circuit is arranged to provide at least one current for charging the DC blocking capacitor. The detection circuit is coupled to a node located between the one of the multiple differential input terminals and the DC blocking capacitor, and is arranged to detect whether an external resistor of the audio amplifier chip exists according to an input voltage from the node, in order to generate a detection result. The control circuit is arranged to determine a start-up time of the audio amplifier according to the detection result.

Abstract: A test tool is used to position a chip on a test circuit board and includes a positioning base and a pressing member. The test circuit board has a plurality of contacts and a probe base with a plurality of probes. The positioning base has a hole for accommodating the chip. The positioning base is positioned on the test circuit board and receives the probe base to make the probes contained in the hole to be connected to the pins and aligned with the contacts. A wall of the hole is formed with two engaging grooves opposite to each other. An engaging end portion of each elastic arm of the pressing member forms a hook protruding toward the engaging groove and presses the chip when the hook is engaged with the engaging groove, for connecting pins of the chip to the contacts via the probes.

Abstract: A controller applied to a servomotor includes a flash memory, a microcontroller, and a processing circuit. The flash memory is arranged to store a first program code for controlling the servomotor. The microcontroller is arranged to determine whether an alarm of the servomotor occurs, wherein in response to the alarm of the servomotor occurring, the microcontroller is arranged to store an error log corresponding to the alarm in the flash memory. In addition, a second program code is programmed into the processing circuit in advance, wherein the second program code is a copied version of the first program code; and in response to the alarm of the servomotor occurring, the processing circuit is arranged to execute the second program code.

Abstract: An audio amplification device includes a charge pump circuit and an operational amplifier. The charge pump circuit generates an output voltage when receiving a power-on reset signal. The operational amplifier has a first input terminal for receiving a first input signal, a second input terminal for receiving a second input signal, a third input terminal for receiving the output voltage, a fourth input terminal for receiving a switching signal output, and an output terminal. The operational amplifier generates an amplified signal at the output terminal according to the first and second input signals, the output voltage and the switching signal output and outputs the amplified signal to a load circuit. When a level of the power-on reset signal changes from a high logic level to a low logic level, the operational amplifier is controlled by the switching signal output to pull a potential of the output terminal to zero.

Abstract: An automatic gain controller includes multiple resistors, multiple switches, a buffer, a charge pump circuit and a voltage level shifter. The resistors are connected in series between an input terminal for receiving an input signal and an inverting input terminal of an operational amplifier. Each of the switches has a first terminal coupled to a corresponding one of the resistors, and a second terminal coupled to the inverting input terminal. The switches are respectively controlled by multiple switching signals so as to be turned on or turned off. The buffer generates a buffer signal according to the voltage at the inverting input terminal. The charge pump circuit generates a boost voltage according to the buffer signal and a clock signal. The voltage level shifter converts voltage levels of multiple control signals according to the buffer signal and the boost voltage to generate and respectively output the switching signals to the switches.

Abstract: A voltage level shifter includes a first voltage regulation unit, a second voltage regulation unit, a first latch unit and an output unit. The first voltage regulation unit and the second voltage regulation unit respectively receive first and second input signals and generate first and second adjustment signals respectively. The first latch unit receives the first and second adjustment signals and generates a first latch signal accordingly. The output unit generates an output signal according to the first latch signal, an input voltage and a control signal. A high logic level voltage of the output signal is greater than the respective high logic level voltages of the first input signal and the second input signal. Wherein, the first voltage regulation unit and the second voltage regulation unit are each a capacitively coupled voltage regulation unit and each includes an input capacitor. The input capacitor has no capacitance to ground at one end.

Abstract: A power stage control circuit applied to a voltage converter includes a current sensing circuit, a control circuit, and a driving circuit, wherein the voltage converter includes a first switch and a second switch. The current sensing circuit senses a current associated with the first switch, and converts current into a sensing voltage. The control circuit performs multiple first logical operations according to the sensing voltage, a second switch driving signal, a zero crossing detection voltage, a compensation voltage, and a reference voltage, in order to generate a modulation signal and a determination signal, for controlling turn-on and turn-off of the first switch and the second switch and dynamically setting an inductor peak current of an inductor, respectively. The driving circuit performs multiple second logical operations according to the modulation signal and the determination signal in order to generate a first switch driving signal and the second switch driving signal.

Abstract: A device for estimating the temperature of a loudspeaker's voice coil includes a signal generator, a signal adjuster, an adder, and a temperature estimator. The signal generator generates and outputs an amplified signal to a loudspeaker according to a measurement signal and an audio signal, and senses a voltage and a current of the amplified signal to generate and output a sensory output. The signal adjuster generates and outputs an inverted signal according to the audio signal. The adder adds the sensory output and the inverted signal to generate a blended signal. The temperature estimator obtains an estimated resistance value of the loudspeaker's voice coil according to the blended signal, and generates a temperature signal according to the estimated resistance value, wherein the temperature signal indicates an estimated temperature value of the loudspeaker's voice coil. Additionally, a method for estimating the temperature of the loudspeaker voice coil is provided.

Abstract: A signal recovery system includes multiple frequency dividers, multiple signal recovery circuits, and a data signal generating circuit. The multiple frequency dividers perform a frequency dividing operation upon a clock signal and a data strobe signal, respectively, to generate a set of frequency-divided clock signals and a set of frequency-divided data strobe signals. The multiple signal recovery circuits perform a signal recovery operation upon the set of frequency-divided clock signals and the set of frequency-divided data strobe signals, respectively, to generate a recovered clock signal and a recovered data strobe signal. The data signal generating circuit generates a data signal according to the recovered clock signal and the recovered data strobe signal, for indicating whether a rising edge of the data strobe signal is located at a first level or a second level of the clock signal, wherein the first level is higher than the second level.

Abstract: An audio amplifier chip includes an audio amplifier, a current providing circuit, a detection circuit, and a control circuit. The audio amplifier is arranged to drive a speaker, wherein the audio amplifier has multiple differential input terminals, and a direct current (DC) blocking capacitor is coupled to one of the multiple differential input terminals. The current providing circuit is arranged to provide at least one current for charging the DC blocking capacitor. The detection circuit is coupled to a node located between the one of the multiple differential input terminals and the DC blocking capacitor, and is arranged to detect whether an external resistor of the audio amplifier chip exists according to an input voltage from the node, in order to generate a detection result. The control circuit is arranged to determine a start-up time of the audio amplifier according to the detection result.

Abstract: A load detection device includes a signal output circuit, comparison circuit, sensing circuit, detection circuit, logic circuit, and control circuit. The signal output circuit outputs a forced current, and generates a bias signal, a first output signal, a second output signal, and a feedback signal depending on the forced current. The comparison circuit compares the reference signal output with the first and second output signals to generate an accurate comparison output for indicating the load state. The sensing circuit generates a sensing signal according to the feedback signal. The detection circuit generates a rough detection output for indicating the load state according to the sensing signal and the first and second output signals. The logic circuit obtains the load state according to the precise comparison output and the rough detection output. The control circuit enables the signal output circuit, comparison circuit, sensing circuit, and logic circuit.

Abstract: Circuit, method for audio signal processing with excursion estimation compensation, and non-transitory storage medium are provided. The circuit comprises a delay circuit, compensation filter, excursion estimator, peak detector, gain determination circuit, and gain adjustment circuit. The delay circuit is for delaying a digital audio signal to output a delayed digital audio signal. The compensation filter is for generating a compensated digital audio signal according to the digital audio signal for excursion estimation compensation for a speaker type. The excursion estimator is for determining an estimated excursion signal for the speaker type according to the compensated digital audio signal. The gain determination circuit is for generating a gain setting signal according to the estimated excursion signal and a threshold value. The gain adjustment circuit is for generating an adjusted digital audio signal according to the gain setting signal and delayed digital audio signal.

Abstract: A write leveling system includes a frequency divider, a signal processing circuit, and a data control circuit. The frequency divider is arranged to perform a frequency dividing operation upon a clock signal to generate multiple frequency-divided clock signals. The signal processing circuit is arranged to perform signal processing upon a data strobe signal to generate multiple processed data strobe signals. The data control circuit is arranged to generate a data signal according to the multiple frequency-divided clock signals and the multiple processed data strobe signals, for indicating whether a rising edge of the data strobe signal is located at a first level or a second level of the clock signal, wherein the first level is higher than the second level.

Abstract: A charger circuit comprises a constant current charging circuit and a thermal regulation circuit. The constant current charging circuit is configured for generating a charging current, including a charger input terminal for receiving an input voltage, a charge current setting terminal, a charger output terminal for outputting the charging current, a current mirror including a reference current path between the charger input terminal and charge current setting terminal and an output current path between the charger input terminal and charger output terminal, and a feedback amplifier having a positive terminal, a negative terminal for receiving a feedback reference voltage, and a feedback output terminal coupled to the current mirror. The thermal regulation circuit is configured for generating and modulating a thermal regulation voltage with temperature, and outputting the thermal regulation voltage across the positive terminal of the feedback amplifier and the charging current setting terminal.

Abstract: A charge pump device includes a voltage adjustment unit, an output capacitor, a first output unit and a second output unit. The voltage adjustment unit performs voltage pumping or voltage reducing operation on a power supply voltage according to first to fourth control signals, a positive pump voltage and an negative pump voltage to generate a first voltage adjustment output and a second voltage adjustment output at a first node and a second node respectively. The output capacitor has a first output terminal and a second output terminal. When the first output unit is turned on, the first voltage adjustment output charges the output capacitor through the first output unit, so that the first output terminal generates the positive pump voltage. When the second output unit is turned on, the second voltage adjustment output charges the output capacitor through the second output unit, so that the second output terminal generates the negative pump voltage.

Abstract: A voltage level shifter includes a first voltage regulation unit, a second voltage regulation unit, a first latch unit and an output unit. The first voltage regulation unit and the second voltage regulation unit respectively receive first and second input signals and generate first and second adjustment signals respectively. The first latch unit receives the first and second adjustment signals and generates a first latch signal accordingly. The output unit generates an output signal according to the first latch signal, an input voltage and a control signal. A high logic level voltage of the output signal is greater than the respective high logic level voltages of the first input signal and the second input signal. Wherein, the first voltage regulation unit and the second voltage regulation unit are each a capacitively coupled voltage regulation unit and each includes an input capacitor. The input capacitor has no capacitance to ground at one end.

Abstract: A charge pump device includes a voltage adjustment unit, an output capacitor, a first output unit and a second output unit. The voltage adjustment unit performs voltage pumping or voltage reducing operation on a power supply voltage according to first to fourth control signals, a positive pump voltage and an negative pump voltage to generate a first voltage adjustment output and a second voltage adjustment output at a first node and a second node respectively. The output capacitor has a first output terminal and a second output terminal. When the first output unit is turned on, the first voltage adjustment output charges the output capacitor through the first output unit, so that the first output terminal generates the positive pump voltage. When the second output unit is turned on, the second voltage adjustment output charges the output capacitor through the second output unit, so that the second output terminal generates the negative pump voltage.