ccts required for low pass filter

Hi,
any idea how to implement or obtain a low-pass filter that filter off 180hz with zero phase change?
also,any ideas for phase-shifter?
thanks.

All filters have phase shift. Tell us what you are trying to accomplish.

so,its not possible to find a filter with zero phase shift?cos i need to find a low pass filter that filter filter off 180hz onwards,while maintaining as much gain of 1 as possible.or else,need to compensate back.also,need to shift back whatever phase change.
can a simple RC cct do that?i need to maintain 1mA into the LPF,so the R may have to be very big....

What is the signal you're trying to filter? Why do you need zero phase shift?