Grid voltage input circuit that samples

The utility model provides a grid voltage input circuit that samples, including a voltage follower circuit unit, level lifting circuit unit, the 2nd voltage follower circuit unit and input protection circuit unit, wherein, the input connection grid voltage incoming signal of a voltage follower circuit unit, be suitable for the output impedance who reduces grid voltage incoming signal, level lifting circuit unit connects first voltage follower circuit unit, be suitable for the signal that will center on zero level fluctuation in the grid voltage incoming signal of voltage follower circuit unit output to promote to the unipolar signal, the 2nd voltage follower circuit unit is suitable for and carries out voltage to the unipolar signal through level lifting circuit unit output with grid voltage incoming signal and follow with reduction output impedance, protection circuit unit is suitable for the abnormal signal of filtration by the output of second voltage follower circuit unit, the utility model discloses can take care of grid voltage to make its requirement that can satisfy follow -up sampling.