| 摘要 |
PURPOSE:To use a filter simple in constitution and of low cost as a low pass filter by connecting a sampling converter before the low pass filter. CONSTITUTION:The sampling converter 23 for converting to a clock frequency lower than the clock frequency fs of a digital signal inputted through a switch 4 is connected to the preceding step of the low pass filter 8. D/A converters 24, 25 for converting the digital signal to an analog signal by a low sampling signal are connected to the succeeding step of the low pass filter 8. Thereby, the quantity of the attenuation of the low pass filter 8 is largely taken, the degree of freedom in designing a filter is increased, a time division processing is executed, the scale of a hardware is reduced and a compactness is attained. |
