Noise characteristics in sigma-delta modulator

시그마 델타변조 방식의 노이즈 특성

Sigma-delta modulation can perform A/D conversion with a high-resolution. It is useful for simplifing the system and spreading out inband signal noise. When the sigma-delta modulation is applied to a switching converter, it can suppress the harmonic frequencies of output signal and be realized with a simple structure. In this paper, some methods of sigma-delta modulation are discussed so as to find the suitable structure for a switching converter. Noise characteristics are calculated and analyzed through simulations.