Abstract: A tray device includes a host module, a tray module, and a communication module communicated between the host module and the tray module. The host module includes a host recognition circuit, a host connection circuit, and a host controller electrically connected to the host recognition circuit and the host connection circuit. The tray module includes a tray recognition circuit, a tray connection circuit, and a tray controller electrically connected to the tray recognition circuit and the tray connection circuit. The tray controller determines an installation ordinal number corresponding to the tray module according to a recognition signal generated by the tray recognition circuit. The tray controller sends the installation ordinal number to the host controller by the communication module when the tray connection circuit generates a connection signal.

Abstract: A tray device includes a host module, a tray module, and a communication module communicated between the host module and the tray module. The host module includes a host recognition circuit, a host connection circuit, and a host controller electrically connected to the host recognition circuit and the host connection circuit. The tray module includes a tray recognition circuit, a tray connection circuit, and a tray controller electrically connected to the tray recognition circuit and the tray connection circuit. The tray controller determines an installation ordinal number corresponding to the tray module according to a recognition signal generated by the tray recognition circuit. The tray controller sends the installation ordinal number to the host controller by the communication module when the tray connection circuit generates a connection signal.

Abstract: A heating roller includes: a roller cylinder rotatably disposed; a base rotatably disposed in the roller cylinder; first to third heaters, which are mounted on the base and respectively have a first heating section, a second heating section and a third heating section extending respectively in directions substantially parallel to an axial direction of the roller cylinder; and a driving mechanism, which is connected to the base and rotates the base to multiple position states. An image forming apparatus using the heating roller is also disclosed.

Abstract: A paper tray includes a casing, a lifting mechanism, a weight detector, a storage unit, and a control unit. An accommodating space is formed inside the casing. The lifting mechanism is disposed inside the accommodating space for supporting and lifting at least one sheet of paper. The weight detector is disposed on the lifting mechanism for detecting a weight of the at least one sheet of paper. The storage unit is for storing paper information and a predetermined amount. The control unit is electrically connected to the weight detector and the storage unit. The control unit determines an amount of the at least one sheet of paper according to relation of the weight and the paper information and outputs a supplementary alert to an apparatus for reminding users when the control unit determines the amount of the at least one sheet of paper is less than the predetermined amount.

Abstract: A heating roller includes: a roller cylinder rotatably disposed; a base rotatably disposed in the roller cylinder; first to third heaters, which are mounted on the base and respectively have a first heating section, a second heating section and a third heating section extending respectively in directions substantially parallel to an axial direction of the roller cylinder; and a driving mechanism, which is connected to the base and rotates the base to multiple position states. An image forming apparatus using the heating roller is also disclosed.

Abstract: A gain controlling system, a sound playback system, and a gain controlling method thereof are disclosed. The gain controlling system includes a main gain control unit, a sub gain control unit, and a logic control unit. The main gain control unit has a first step-by-step adjusting magnitude; the sub gain control unit has a second step-by-step adjusting magnitude; wherein the second step-by-step adjusting magnitude is smaller than the first step-by-step adjusting magnitude. The logic control unit is used for controlling the main and the sub gain control unit to transform an analog signal into a converted signal according to an adjustment command signal and further determining whether an adjusting magnitude required by the adjustment command signal is larger than a maximum gain range of the sub gain control unit. If yes, the logic control unit controls the main control unit and the sub gain control unit repeatedly.

Abstract: An amplifying circuit capable of suppressing spikes of an audio signal includes an integration module, a comparison module, an output module, a feedback module, and a limiting module. The integration module is used for receiving an input signal and generating a first voltage signal corresponding to the input signal. The comparison module is coupled to the integration module for receiving the first voltage signal and a reference signal, and generating a comparison signal. The output module is coupled to the comparison module for generating an audio signal according to the comparison signal. The feedback module is coupled between the output module and the integration module for feeding back an output signal to the integration module. The limiting module is coupled between the feedback module and the integration module for limiting the comparison signal to be within a predetermined range.

Abstract: A gain controlling system, a sound playback system, and a gain controlling method thereof are disclosed. The gain controlling system includes a main gain control unit, a sub gain control unit, and a logic control unit. The main gain control unit has a first step-by-step adjusting magnitude; the sub gain control unit has a second step-by-step adjusting magnitude; wherein the second step-by-step adjusting magnitude is smaller than the first step-by-step adjusting magnitude. The logic control unit is used for controlling the main and the sub gain control unit to transform an analog signal into a converted signal according to an adjustment command signal and further determining whether an adjusting magnitude required by the adjustment command signal is larger than a maximum gain range of the sub gain control unit. If yes, the logic control unit controls the main control unit and the sub gain control unit repeatedly.

Abstract: A class-D power amplifier capable of reducing electromagnetic interference includes an integrator, a triangular wave generator, a comparator, a gate driver, a feedback circuit, and an output stage circuit. The integrator is used for receiving an input signal and potential of ground, and outputting a first voltage. The comparator is used for comparing the first voltage with a triangular wave generated by the triangular wave generator to output a pulse-width modulation signal. The gate driver is used for driving the output stage circuit to output an output voltage according to the pulse-width modulation signal. Therefore, the class-D power amplifier reduces the electromagnetic interference by the triangular wave.

Abstract: A class-D power amplifier capable of reducing electromagnetic interference includes an integrator, a triangular wave generator, a comparator, a gate driver, a feedback circuit, and an output stage circuit. The integrator is used for receiving an input signal and potential of ground, and outputting a first voltage. The comparator is used for comparing the first voltage with a triangular wave generated by the triangular wave generator to output a pulse-width modulation signal. The gate driver is used for driving the output stage circuit to output an output voltage according to the pulse-width modulation signal. Therefore, the class-D power amplifier reduces the electromagnetic interference by the triangular wave.

Abstract: An amplifying circuit capable of suppressing spikes of an audio signal includes an integration module, a comparison module, an output module, a feedback module, and a limiting module. The integration module is used for receiving an input signal and generating a first voltage signal corresponding to the input signal. The comparison module is coupled to the integration module for receiving the first voltage signal and a reference signal, and generating a comparison signal. The output module is coupled to the comparison module for generating an audio signal according to the comparison signal. The feedback module is coupled between the output module and the integration module for feeding back an output signal to the integration module. The limiting module is coupled between the feedback module and the integration module for limiting the comparison signal to be within a predetermined range.

Abstract: An audio playback apparatus is disclosed. The audio playback apparatus processes an audio signal and provides at least one output signal to at least one speaker or an earphone connected to a phone-jack. The audio playback apparatus comprises a clock generating module, a processing module, an amplifier module, and a detecting module. The processing module is connected to the clock generating module and processes the audio signal to generate a processed signal according to a clock signal generated by the clock generating module. The amplifier module amplifies the processed signal to generate an output signal. The detecting module detects whether the earphone is plugged in the phone-jack. If the earphone is plugged in the phone-jack, the amplifier module provides the output signal to the earphone. If not, the amplifier module provides the output signal to the speaker.

Abstract: An audio control apparatus. The audio control apparatus comprises a processing module, an amplification module, and a control module. The processing module receives and processes an audio signal according to a control signal, and generates a processed signal. The amplification module coupled to the processing module, amplifies the processed signal to generate an output signal. The control module coupled to the processing module and the amplification module, receives the output signal to generate the control signal.

Abstract: An audio signal processing apparatus is provided. The audio signal processing apparatus comprises a clock generator, a processing module, an amplifying module and an output module. The clock generator is used for generating a clock signal. The processing module is coupled to the clock generator for processing the clock signal and generating a processing signal. The amplifying module is coupled to the processing module for amplifying the processing signal and generating an amplifying signal. The output module is coupled to the amplifying module for outputting the amplifying signal.

Abstract: An audio amplifier includes a plurality of sub-audio amplifier sets, a clock source, and a speaker. When the audio amplifier is under an audio amplify mode, the plurality of sub-audio amplifier sets is operated under a synchronic operating frequency with a same clock signal generated by the clock source. When the audio amplifier is under a self-oscillation mode, the clock signal is isolated from being input to the plurality of sub-audio amplifier sets. A higher distortion is prevented by repeatedly charging and discharging an oscillating capacitor of a sub-audio amplifier in a sub-audio amplifier set.

Abstract: In a speaker system, pulse width modulation signals are utilized for driving said speaker system, and duty cycles of both left audio channel signals and right audio channel signals of an earphone in said speaker system are modulated by said pulse width modulation signals. When the left audio channel or the right audio channel of the earphone has no inputted audio signals with the abovementioned modulated duty cycles, the speaker system may be prevented from unnecessary power consumption. Besides, audio signals from both the left audio channel and the right audio channel of the earphone and outputted from the speaker system may thus be synchronized further by both the pulse width modulation signals and a sawtooth wave source for generating said pulse width modulation signals, for reducing noise and increasing an output audio quality of the speaker system. The abovementioned speaker system is preferably utilized for a Class D amplifier.

Abstract: The invention provides an integrated circuit for reducing radio frequency interference due to antenna effects. In one embodiment, the integrated circuit includes a pre-stage audio processor and a post-stage power amplifier. The pre-stage audio processor receives a left channel input signal and a right channel input signal, processes the left channel input signal to obtain a positive left channel signal and a negative left channel signal, and processes the right channel input signal to obtain a positive right channel signal and a negative right channel signal. The post-stage power amplifier amplifies the positive left channel signal and the negative left channel signal to obtain a left channel output signal, and amplifies the positive right channel signal and the negative right channel signal to obtain a right channel output signal.

Abstract: An audio playback apparatus is disclosed. The audio playback apparatus processes an audio signal and provides at least one output signal to at least one speaker or an earphone connected to a phone-jack. The audio playback apparatus comprises a clock generating module, a processing module, an amplifier module, and a detecting module. The processing module is connected to the clock generating module and processes the audio signal to generate a processed signal according to a clock signal generated by the clock generating module. The amplifier module amplifies the processed signal to generate an output signal. The detecting module detects whether the earphone is plugged in the phone-jack. If the earphone is plugged in the phone-jack, the amplifier module provides the output signal to the earphone. If not, the amplifier module provides the output signal to the speaker.

Abstract: An audio signal processing apparatus is provided. The audio signal processing apparatus comprises a clock generator, a processing module, an amplifying module and an output module. The clock generator is used for generating a clock signal. The processing module is coupled to the clock generator for processing the clock signal and generating a processing signal. The amplifying module is coupled to the processing module for amplifying the processing signal and generating an amplifying signal. The output module is coupled to the amplifying module for outputting the amplifying signal.

Abstract: An audio control apparatus. The audio control apparatus comprises a processing module, an amplification module, and a control module. The processing module receives and processes an audio signal according to a control signal, and generates a processed signal. The amplification module coupled to the processing module, amplifies the processed signal to generate an output signal. The control module coupled to the processing module and the amplification module, receives the output signal to generate the control signal.