PURPOSE: To attain multiplexing of a quantization loop by providing a sample- and-hold circuit, an input changeover switch and a storage circuit.
CONSTITUTION: A switch 100 switching an input signal Vin and an output of a sample-and-hold circuit, an input adder 101, an integration device 102 having plural (N) number of integration capacitors Ci1∼CiN switched a t a prescribed timing, an adder 103, and a quantizer (Q) 104 comprising an A/D converter or the like are provided and they are connected sequentially in series. The input of one adder 101 is connected to the other adder 103. A decoder 105 com prising a D/A converter or the like generating a feedback signal is connected between the output of the quantizer 104 and the adder 101 and a sample-and-hold circuit 106 sampling the output of the integrator and holding the result is con nected between the switch 100 and the output of the integration device 102. Further, the storage circuit 107 storing sequentially the output of the quantizer is connected to the output side of the quantizer 104 and a differentiation circuit 108 and the adder 109 are connected to the output side of the storage circuit 107.
YANAGA OSAMU
ARAI TOSHIO
UCHIMURA KUNIHARU
HAYASHI TOSHIO
KIMURA TADAKATSU
NIPPON TELEGRAPH & TELEPHONE