Hi everybody,

Recently I have set up a circuit to detect the phase error between the two signal,but no matter how I change the phase error of the input signal,the voltage of Vphs pin is constant about 0.9V rather than a linear change,I'd like to know what happened.

The basic condition of my circuit is as follows:

C1=C4=C5=C6=10uF,C2=C8=1uF,C3=100pF,C7=0.1uF,R1=R2=52.3Ohms.

The frequency of input signal is 500Hz,Vpp of the two sine signal is 10V

Thank you very much for your help!

You are over driving the part, in fact you may have damaged it with 10Vpp.

Maximum operation signal level on the input is 0 dBm, which is .223 Vrms or 631 mVpp. What you really want for maximum dynamic range is to have one input at -30 dBm, or about 20mVpp and vary the other input +/- 30 dB around that.