I would like to design a cic filter as shown in the picture attach. The comb part is differentiator and the other part on the right is integrator. However i do not now how to implement the upsample (L).. I try to build it with simulink where the upsample(L) is a switch operate at higher sampling rate. but due to the integrator which act as accumulator, the amplitude at the output is high. For example i apply a sin wave with amplitude=0.5..although i can get a higher sampling rate at the output but the amplitude is 3k ++...any body can help with this design? thanks in advance

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