Novel digital microphone test circuit, test system and test method

The invention discloses a novel digital microphone test circuit, test system and method, which are simple in structure, high in test precision and low in cost. The circuit comprises an acquisition module (1), a decoding unit (2) and an MCU unit (3); the acquisition module (1) is connected with a microphone to be tested and the MCU unit (3), the decoding unit (2) is connected with the MCU unit (3),and the MCU unit (3) is connected with a peripheral processor. The system further comprises a silencing chamber (7) and a processor (8), and a loudspeaker (9) is further arranged in the silencing chamber (7). The test method comprises the following steps the acquisition module acquires a PDM signal and uploads the PDM signal to the MCU unit (3), the decoding unit decodes the PDM signal into a PCMsignal, the MCU unit (3) transmits the PCM signal to the processor (8), and the processor (8) obtains the frequency and sensitivity of a microphone signal through Fourier transform. The method can beapplied to the test field.