The present invention proposes an audio signal muting apparatus setting and adjusting a time for removing pop noise and muting an audio signal based on the set and adjusted timing. Further, the present invention proposes a digital signal converting apparatus for muting an analog audio signal based on a timing for removing pop noise when converting a digital audio signal into an analog audio signal in connection with an audio signal reproducing apparatus.

Embodiments provide a device for removing noise of a power source and an apparatus for converting an audio signal, which remove a noise component which comes from a power source terminal of an audio signal converting apparatus stepwise and transfer power to a converting unit and an amplification unit included in the audio signal converting apparatus from a power source terminal to remove power noise.

The present invention is a modular signal converting apparatus and method, and particularly, discloses a signal converting apparatus, which is modularized for playback of digital contents and is usable while being combined with another electric device.

A headset accessory comprises circuitry and is configured to mechanically attach to an audio headset. The circuitry of the headset may be operable to establish a link to the audio headset that supports conveyance of bias voltage, bias current, and/or information between the circuitry of the accessory and circuitry of the audio headset. The headset accessory may be configured to attach to a housing of the headset on a surface of the housing opposite an ear cup. A state of the circuitry of the accessory may be controlled based on the information received from the audio headset via the link. The information may include characteristics of audio being processed by the audio headset. The circuitry of the headset accessory may comprise non-volatile memory, and the non-volatile memory may store parameter settings for configuring audio processing circuitry of the audio headset.

The embodiments provide an apparatus for converting an audio signal, in which a left channel line and a right channel line connected to an amplification unit of an audio signal converting apparatus are covered with the ground and connected to a chassis of the audio signal converting apparatus, and a digital signal line and an analog signal line are disposed to be spaced apart from a substrate to improve crosstalk and remove noise.

Embodiments provide a device for removing noise of a power source and an apparatus for converting an audio signal, which remove a noise component which comes from a power source terminal of an audio signal converting apparatus stepwise and transfer power to a converting unit and an amplification unit included in the audio signal converting apparatus from a power source terminal to remove power noise.

Various embodiments relate to a method for calibration of a center frequency of a BPF in an FSK transceiver, the method including the steps of filtering a carrier frequency signal by the BPF to produce a filtered signal, detecting, by a phase-frequency detector (PFD), a difference in phase between the carrier frequency signal and the filtered signal from the BPF, sweeping a calibration code of the BPF, detecting a transition in the sign of the phase difference and capturing a calibration code associated with the transition in the sign of the phase difference for calibration of the BPF.

A headset accessory comprises circuitry and is configured to mechanically attach to an audio headset. The circuitry of the headset may be operable to establish a link to the audio headset that supports conveyance of bias voltage, bias current, and/or information between the circuitry of the accessory and circuitry of the audio headset. The headset accessory may be configured to attach to a housing of the headset on a surface of the housing opposite an ear cup. A state of the circuitry of the accessory may be controlled based on the information received from the audio headset via the link. The information may include characteristics of audio being processed by the audio headset. The circuitry of the headset accessory may comprise non-volatile memory, and the non-volatile memory may store parameter settings for configuring audio processing circuitry of the audio headset.

The present invention proposes an audio signal muting apparatus setting and adjusting a time for removing pop noise and muting an audio signal based on the set and adjusted timing. Further, the present invention proposes a digital signal converting apparatus for muting an analog audio signal based on a timing for removing pop noise when converting a digital audio signal into an analog audio signal in connection with an audio signal reproducing apparatus.

A line output converter (LOC) combined with a microprocessor to sense LOC output signal strength and respond to usefully high levels by generating a trigger to turn on an amplifier that is receiving the LOC output signal. A short, first predetermined time is programmed into the microcontroller as a minimum time to sense high signal levels before activating the amplifier, in order to suppress transient signals. A longer, second predetermined time is programmed into the microcontroller as a minimum time to sense low signal levels before deactivating the amplifier. The predetermined boundary between a high and a low signal level is also programmed into the microcontroller and, as with the predetermined times, is established responsive to the characteristics of the particular LOC involved. In an embodiment, the LOC is a compact adjustable LOC located on the same PCB as the microcontroller.