Patent ID: 8711917

Claim:
A sampling filter device comprising: a first voltage current converter which converts an input voltage signal into a current; a first integration unit which samples the current output from the first voltage current converter and integrates the sampled current; a local oscillator which outputs a reference clock; an integration time duration control unit which generates an integration time duration control signal for controlling integration time duration in the first integration unit based on the reference clock, and makes the integration time duration variable, thereby performing weighting of a filter characteristic of the sampling filter device in response to the variable integration time duration; and a second voltage current converter arranged in parallel with the first voltage current converter and having a gain different from that of the first voltage current converter, wherein the first integration unit samples the current output from the first voltage current converter or the second voltage current converter, and integrates the sampled current, and integration charge amount per unit time in the first integration unit is varied by switch control of the first voltage current converter and the second voltage current converter.