The invention relates to a pulse width modulator, more particularly to a cross-coupled pulse width modulator. A crossing input signal modulator according to the present invention comprises: a positive path block which includes a first integrator for performing the first-order integration of feedback signals in first input and output signals and then transmitting the first-order integrated signals to a second integrator, and a second integrator for performing the second-order integration of a signal from the first integrator and a second input signal and then transmitting the second-order integrated signals; and a negative path block which includes a third integrator for performing the first-order integration of feedback signals in the second input and output signals and integration of a signal from the third integrator and the first input signal and then transmitting the second-order integrated signals. This configuration allows cross-coupling of the inputs from two integrators to generate an accurate differential pulse width modulation (PWM) single, and enables optimization of the IC implementation by adopting a feedback system that features a simplified implementation and minimal application area.