HMC984: How to use it as a phase detector?

Hi, everyone! I know the HMC984 is a charge pump PFD and i'm wondering the way to use it to measure the phase error between two input signal REF and VCO.

- First, can i make the assumption that +phase error corresponding to sourse current and -phase error corresponding to sink current? And the pulse width is decided by the phase error.

- Second, if i use a passive loop filter , is it possible to get a negative voltage that represents the -phase error at the output of the filter . If not , is it possible to implement this with a passive loop filter and how to realize it?

Thanks for help!