Frequency Limits on Low-Pass Filter and BandPass Filter User Modules

Question: What are the upper and lower limits of input signal frequency of the low-pass filter and the band-pass filter user modules, at all the different power levels?

 

Answer:

The cut-off frequencies of the LPF and BPF are:                                                                                 

Maximum cut-off frequency = 250kHz                                                                                                                     Min cut-off frequency = 300Hz

For the Bandpass Filter the passband can be anywhere in between the max and min spec. The lower limit for both of the filters is due to leakage in the sample and hold circuitry. The upper limit is do to the finite bandwidth of the operational amplifiers in the SC Blocks.

The bandwidth for low power is up to 10kHz. Medium power gives a bandwidth of up to 15kHz. High power gives a bandwidth of up to 250kHz. At frequencies above 50kHz, op amp bias should be set to "High" in the global parameters window of PSoC Designer.