| 摘要 |
PURPOSE:To lessen an error of a quantization step and reduce a quantizing noise, even in case of a small amplitude signal, by providing a direct current portion addition means on the prestage or the poststage of a sampling hold circuit. CONSTITUTION:A sound signal which has been provided to the terminal 1 is sampled, being based on a sampling pulse provided to the sampling pulse input terminal 3, in the sampling hold circuit 2, and it is held to a constant value. An output signal of the circuit 2, and voltage supplied from the DC input terminal 5 are added by the adder circuit 4, and are provided to the A/D converting circuit 6. In this circuit 6, an input signal is quantized in accordance with a pulse from the start convert pulse input terminal 7, and a digital output signal is sent out to the output terminal 8. |
