| 摘要 |
<p>PURPOSE:To drive a digital speaker without the need for a switching circuit for the polarity switching and a signal for polarity discrimination. CONSTITUTION:When signals are converted into the signals in n-bit at an A-D converter 11, the conversion is made in accordance with the 2's complement binary system. In this system, this binary signal is directly supplied to a speaker 9. In this case, signals applied to coils 7b-d are of the same polarity with each other and the signals applied to a coil 7a are of the opposite polarity with the above mentioned signals by selecting the direction of current and the winding direction of the coils. Through this constitution, when the quantized value is of the positive polarity, the quantization is the same as conventional systems, but when the value is of negative polarity, the quantized value of the most significant bit is always, e.g., -8,, then the value is subtracted with the quantized value of other remaining bits and the operation of the desired quantized value can be made at the speaker 9 in itself.</p> |
