| 摘要 |
PROBLEM TO BE SOLVED: To provide a digital filter circuit configured in multi-stages with its circuit scale reduced so that parameter setting and degree of the filter can be changed. SOLUTION: The digital filter circuit comprises: a digital filter arithmetic circuit comprising multipliers 1 to 5, adders 7, 9, 19, and registers 8, 9; a register 10 for latching an output of the digital filter arithmetic circuit; a selector 17 for selecting a sample value input or an output of a feedback register as an input to the digital filter arithmetic circuit; and registers 11 to 15 the number of which is the same as that of the multipliers holding multiplication coefficients given to the multipliers, values held in the registers 8, 9 are saved after activating the digital filter arithmetic circuit, and the values saved in the registers 8, 9 are restored before activating the digital filter arithmetic circuit. COPYRIGHT: (C)2004,JPO
|
