Abstract: The present disclosure illustrates a button detecting circuit and method thereof. The button detecting circuit includes a determining circuit, a voltage selector and a button module. The voltage selector is electrically connected to the determining circuit. The voltage selector has a plurality of candidate voltages arranged in sequence based on magnitudes of the candidate voltages. The button module which is electrically connected to the determining circuit via a single one pin comprises a threshold unit and a button network. The determining circuit receives the candidate voltage outputted from the voltage selector and outputs the candidate voltage to the button module for testing whether the threshold unit will be conducted to find a threshold voltage. The button module generates a scanning current based upon the threshold voltage. The determining circuit senses the scanning current and determines which one of a plurality of buttons disposed in the button network is pressed.

Abstract: The invention provides an analog-to-digital converter. In one embodiment, the analog-to-digital converter receives a first audio signal from a microphone, and comprises a coding selection module, a pre-amplifier, a 1-bit ?? modulator, and a signal coding module. The coding selection module receives a mode signal and a channel selection signal, and generates a control signal according to the mode signal and the channel selection signal. The pre-amplifier amplifies the first audio signal to obtain a second audio signal. The 1-bit ?? modulator converts the second audio signal from analog to digital to obtain a third audio signal.

Abstract: The invention provides a sound processing device. In one embodiment, the sound processing device comprises a first microphone, a first analog-to-digital converter, a second microphone, and a second analog-to-digital converter. The first microphone detects a first sound pressure to generate a first analog audio signal. The first analog-to-digital converter converts the first analog audio signal from analog to digital to obtain a first digital audio signal. The second microphone detects a second sound pressure to generate a second analog audio signal.

Abstract: The invention provides an analog-to-digital converter. In one embodiment, the analog-to-digital converter receives a first audio signal from a microphone sensor, and receives a first channel selection signal and a clock signal, and comprises a toggle detection module, a first data processing module, a second data processing module, and a multiplexer. The toggle detection module detects whether the first channel selection signal is toggling between a logic low level and a logic high level to generate a control signal. The first data processing module processes the first channel selection signal to generate a second channel selection signal. The second data processing module converts the first audio signal from analog to digital to generate a second audio signal.

Abstract: The invention provides a sound processing device. In one embodiment, the sound processing device comprises a first microphone, a first analog-to-digital converter, a second microphone, and a second analog-to-digital converter. The first microphone detects a first sound pressure to generate a first analog audio signal. The first analog-to-digital converter converts the first analog audio signal to a first digital audio signal. The second microphone detects a second sound pressure to generate a second analog audio signal. The second analog-to-digital converter converts the second analog audio signal to a second digital audio signal, encodes a third digital audio signal according to the second digital audio signal, receives the first digital audio signal and a clock signal, outputs data bits of the third digital audio signal when the clock signal oscillates to a logic low level, and outputs data bits of the first digital audio signal when the clock signal oscillates to a logic high level.

Abstract: The invention provides an analog-to-digital converter. In one embodiment, the analog-to-digital converter receives a first audio signal from a microphone, and comprises a coding selection module, a pre-amplifier, a 1-bit ?? modulator, and a signal coding module. The coding selection module receives a mode signal and a channel selection signal, and generates a control signal according to the mode signal and the channel selection signal. The pre-amplifier amplifies the first audio signal to obtain a second audio signal. The 1-bit ?? modulator converts the second audio signal from analog to digital to obtain a third audio signal.

Abstract: The invention provides a sound processing device. In one embodiment, the sound processing device comprises a first microphone, a first analog-to-digital converter, a second microphone, and a second analog-to-digital converter. The first microphone detects a first sound pressure to generate a first analog audio signal. The first analog-to-digital converter converts the first analog audio signal from analog to digital to obtain a first digital audio signal. The second microphone detects a second sound pressure to generate a second analog audio signal.

Abstract: The invention provides an analog-to-digital converter. In one embodiment, the analog-to-digital converter receives a first audio signal from a microphone sensor, and receives a first channel selection signal and a clock signal, and comprises a toggle detection module, a first data processing module, a second data processing module, and a multiplexer. The toggle detection module detects whether the first channel selection signal is toggling between a logic low level and a logic high level to generate a control signal. The first data processing module processes the first channel selection signal to generate a second channel selection signal. The second data processing module converts the first audio signal from analog to digital to generate a second audio signal.

Abstract: The invention provides a sound processing device. In one embodiment, the sound processing device comprises a first microphone, a first analog-to-digital converter, a second microphone, and a second analog-to-digital converter. The first microphone detects a first sound pressure to generate a first analog audio signal. The first analog-to-digital converter converts the first analog audio signal to a first digital audio signal. The second microphone detects a second sound pressure to generate a second analog audio signal. The second analog-to-digital converter converts the second analog audio signal to a second digital audio signal, encodes a third digital audio signal according to the second digital audio signal, receives the first digital audio signal and a clock signal, outputs data bits of the third digital audio signal when the clock signal oscillates to a logic low level, and outputs data bits of the first digital audio signal when the clock signal oscillates to a logic high level.

Abstract: An audio processing circuit is provided, receiving a microphone signal from a microphone to output a differential signal. A preamplifier receives the microphone signal to output a first preamplified voltage and a second preamplified voltage. A gain stage receives the first preamplified voltage and the second preamplified voltage to output the differential signal comprising a first differential output and a second differential output. In the preamplifier, a first operational amplifier is provided. A first voltage controlled current source is controlled by the output end of the first operational amplifier to provide a first current. A first transistor has a gate coupled to a ground voltage supply, a source coupled to the first voltage controlled current source for receiving the first current, and a drain coupled to a voltage ground. Likewise, a second voltage controlled current source and a second transistor are presented symmetrically to render the differential output.

Abstract: An audio processing circuit is provided, receiving a microphone signal from a microphone to output a differential signal. A preamplifier receives the microphone signal to output a first preamplified voltage and a second preamplified voltage. A gain stage receives the first preamplified voltage and the second preamplified voltage to output the differential signal comprising a first differential output and a second differential output. In the preamplifier, a first operational amplifier is provided. A first voltage controlled current source is controlled by the output end of the first operational amplifier to provide a first current. A first transistor has a gate coupled to a ground voltage supply, a source coupled to the first voltage controlled current source for receiving the first current, and a drain coupled to a voltage ground. Likewise, a second voltage controlled current source and a second transistor are presented symmetrically to render the differential output.

Abstract: A microphone preamplifier circuit is provided in a system on chip. An amplifier comprises a first input end, a second input end, and an output end. A bias voltage is provided by a bias voltage source. A first sensor is coupled to the first input end and the bias voltage source for sensing a first physical parameter and a second physical parameter. A second sensor is coupled to the second input end and the bias voltage source for sensing the first physical parameter, wherein the second sensor is insensitive to the second physical parameter. The output end of the amplifier outputs a difference of the first and second input ends whereby noises and interferences are reduced.

Abstract: A microphone preamplifier circuit is provided. An amplifier comprises a first input end, a second input end, and an output end. A bias voltage is provided by a bias voltage source. A first sensor is coupled to the first input end and the bias voltage source for sensing a first physical parameter and a second physical parameter. A second sensor is coupled to the second input end and the bias voltage source for sensing the first physical parameter, wherein the second sensor is insensitive to the second physical parameter. The output end of the amplifier outputs a difference of the first and second input ends whereby noises and interferences are reduced.

Abstract: A temperature measurement circuit has a current excitation circuit, a temperature calculation circuit, a calibration factor generator, and an analog-to-digital conversion circuit. The current excitation circuit supplies in sequence at least two currents to a thermal sensor. At least two output signals are correspondingly generated from the thermal sensor. In response to the at least two output signals, the temperature calculation circuit calculates an analog temperature signal representative of a temperature detected by the thermal sensor. The analog-to-digital conversion circuit converts the analog temperature signal into a digital signal based on a conversion reference level. The conversion reference level is shifted in accordance with a calibration value generated from the calibration factor generator.

Abstract: A rail-to-rail operational amplifier is provided with a high-side current adjusting circuit and a low-side current adjusting circuit. On a basis of a comparison between a first input voltage and a second input voltage, the high-side current adjusting circuit adjusts a high-side bias current. Under a condition that the first input voltage is smaller than the second input voltage, the high-side current adjusting circuit increases the high-side bias current when an absolute value of a difference between the first and the second voltages increases. On a basis of the comparison between the first and the second input voltages, the low-side current adjusting circuit adjusts a low-side bias current. Under a condition that the first input voltage is larger than the second input voltage, the low-side current adjusting circuit increases the low-side bias current when the absolute value of the difference between the first and the second voltages increases.

Abstract: A rail-to-rail operational amplifier is provided with a high-side current adjusting circuit and a low-side current adjusting circuit. On a basis of a comparison between a first input voltage and a second input voltage, the high-side current adjusting circuit adjusts a high-side bias current. Under a condition that the first input voltage is smaller than the second input voltage, the high-side current adjusting circuit increases the high-side bias current when an absolute value of a difference between the first and the second voltages increases. On a basis of the comparison between the first and the second input voltages, the low-side current adjusting circuit adjusts a low-side bias current. Under a condition that the first input voltage is larger than the second input voltage, the low-side current adjusting circuit increases the low-side bias current when the absolute value of the difference between the first and the second voltages increases.

Abstract: A temperature measurement circuit has a current excitation circuit, a temperature calculation circuit, a calibration factor generator, and an analog-to-digital conversion circuit. The current excitation circuit supplies in sequence at least two currents to a thermal sensor. At least two output signals are correspondingly generated from the thermal sensor. In response to the at least two output signals, the temperature calculation circuit calculates an analog temperature signal representative of a temperature detected by the thermal sensor. The analog-to-digital conversion circuit converts the analog temperature signal into a digital signal based on a conversion reference level. The conversion reference level is shifted in accordance with a calibration value generated from the calibration factor generator.