| 摘要 |
Apparatus for converting an analogue signal 1 to digital form includes an A/D convertor 4 having insufficient digits for the accuracy required, a prediction circuit 5 providing a prediction 8 of the input signal based on previous cycles, and means 2 for calculating an error signal from the input signal 1 and the prediction 8 and feeding the error signal to the A/D convertor 4. An output of improved accuracy is obtained by adding, 11, the error signal from the A/D convertor 4 to the prediction 8 to generate an output. The prediction circuit 5 may include a second adder receiving the outputs of delay 7 and a delay connected to the output of adder 11, the output of this second adder being supplied to a rounding circuit which feeds the adder 11 and D/A converter 9. <IMAGE> |
