| 摘要 |
<p>PURPOSE:To convert microphone outputs into binary codes easily by sequentially comparing an output voltage, developed by the capacity variation of each capacitor microphone element, with different reference voltages. CONSTITUTION:When output V0 is assumed to be obtained from each capacitor microphone element 9 applied with sound pressure, the output of transducer A is compared with V0. In this case, the code output of transducer circuit A is ''1'', and code outputs of transducer circuits B and C are ''0''. Further, when the microphone output is 2V0, the output of circuit B is ''1''. Since switch SWB is closed by the output of comparing circuit 10 of this circuit B to apply reference voltage 2V0 by the adder of circuit A, circuit A outputs ''0'' and binary code outputs are ''0'', ''1'' and ''0'' respectively. Similarly, when the microphone output is 3V0, code outputs are ''0'', ''1'' and ''1'' and when 4V0, switch SWC is put into operation to generate code outputs ''1'', ''0'' and ''0''.</p> |
