| 摘要 |
PROBLEM TO BE SOLVED: To obtain a low-noise, high-dynamic range digital microphone digitally outputting a sound signal directly from a microphone unit, eliminating an amplifier circuit, a buffer circuit and a differential signal circuit. SOLUTION: The digital microphone includes aΔΣmodulator to output a digital signal. TheΔΣmodulator has a membrane 10 vibrating with sound waves, a resonator 12 with a wiring pattern disposed opposite to the membrane 10, an oscillator outputting an FM signal according to the vibration of the membrane 10 with the provision of the resonator 12 and a one-bit quantizer 18 sampling the FM signal with a high-frequency pulse to output a one-bit quantized signal. COPYRIGHT: (C)2009,JPO&INPIT
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