Differential Active Band pass filter design

Arvind,

You may have a hard time finding op amps to use in such a design, but I won't discourage you yet.

I need some more information: what stopband attenuation do you need, and where does the the stopband need to start? I'm looking for something like "I need -40dB at 180MHz" or something like that. With that information, I may be able to suggest a design.

following stopband attenuation ok for my differential active BPF  design-

                                                                    stopband attenuation   @  185 MHz  = -3dB                  and    @  135 MHz  = -3dB

                                                                                                              @ 190 MHz  = -15dB                 and    @ 130 MHz  = -15dB

                                                                                                               @ 200 MHz  =  -50dB                 and        @ 120 MHz  =  -50dB

I'm working on this, will post a possible solution in the next day or so.

is there possiblity  to  design active LOW PASS Filter with  such high, 50  MHz bandwith?

Yes, there is.

I did a design in FilterPro, using a 5MHz cutoff frequency, then scaled the resistors so that the cutoff was in fact 50MHz. Here's the design:

The frequency response is:

There is a slight peaking, so this may need a little tweaking. I wasn't sure what attenuation you needed at what frequency, but judging from your bandpass requirements, I opted for a 10th order filter. 

I've attached the TINA-TI schematic file to this so you can experiment with it in TINA-TI.

5811.lowpass_hf.tsc