R/D converter and angle detection apparatus

摘要

A band elimination filter 35 that eliminates or reduces a low frequency noise superposed on resolver signals S 1 and S2 is provided between a synchronous detection circuit 34 that performs synchronous detection by referring to an excitation signal and a controller 36 that controls a digital angle output ϕ to make a deviation (sin (θ - ϕ)), which is the output of the synchronous detection circuit, zero.