Sawtooth generator using two triangular waves

Switching regulator is used in many electronics devices because of its small size and low power consumption. Sawtooth wave is one of the important components of the switching regulator and determines the accuracy of the duty ratio of the switching regulator. When the sawtooth wave has fall time, the duty ratio has an error. In this paper, method to realize sawtooth wave generator which has slight fall time, less amplitude error, and less oscillation frequency error compared with conventional circuit, is proposed. The proposed circuit achieves these features by using two triangular waves exclusively. Spectre simulations are performed to verify the validity of the proposed method.