is it possible to use the Digital Filter User module in psoc 5 more than once. I mean more than one filter per design .

I'm a bit unsure, but doesn't have the filter-block two independent channels? So we already have two filters.

Bob 

Yes, but  we can always create our own components in PSoC Right....! All what am I saying is, If  cypress has already written the code for a digital  filter. Why can't we use the same for invoking the required number of filters if we have the required number of UDB's at our disposal. 

2. Or do we have to manually write code for a filter in verilog to implement it.

3. Can we change the cutoff frequency by some external means while the Digital filter is at work.

I'm afraid that will not work. If you look into the report-file of your project, there is a DFB (Digital Filter Block) and there is only one. This is where the Filter-component is made of.

To get more filters you have to use the "conventional" way, use op-amps and external components.

Bob

 Thank you Bob. what about the cut off frequency of the filter block (DFB). Is there a way to change it by external or internal means.

I am a digital man, so I think, the only way to increase the upper frequency limit is to increase the clock to its allowed maximum (whatever that is).

Bob

The frequency response the PSoC digital filter can be found in the digital filter specification.

For a digital filter the upper frequency limit acccording to Nyquist sampling theory is 1/2 of the sample rate.

The filter block or the Digital Filter Block in PSoC3/PSoC5 is hardwrae block and it is not sunthesided in the UDB. It is like a microcontroller with its own set of assembly instructions and datapath. The DFB component available in PSoC Creator lets you create different filters, what the component does is it generates the code requires for implementing the filter that is designed in the GUI configuration wizard, assembles the same code and puts it in the appropraite place. There are 2 filter channels in the DFB component. Please go throught the component datsheet to understand the component better.