Patent ID: 7741887

Claim:
A triangular wave generator, comprising: two triangular wave oscillation circuits generating triangular waves with phases opposite to each other; and a slope switching circuit monitoring an output voltage of each of the two triangular wave oscillation circuits, to switch an output voltage generation mode of one of the two triangular wave oscillation circuits, from an up-slope waveform mode to a down-slope waveform mode, when an output voltage of the one of the two triangular wave oscillation circuits reaches a reference upper limit crest value, and to switch an output voltage generation mode of other of the two triangular wave oscillation circuits, from the down-slope waveform mode to the up-slope waveform mode; and an oscillation level control circuit controlling an oscillation level of the other of the two triangular wave oscillation circuits so that the output voltage of the other of the two triangular wave oscillation circuits becomes a reference lower limit crest value during switching of the output voltage generation mode, wherein the two triangular wave oscillation circuits are capable of independently controlling oscillation levels of the triangular waves generated by the two triangular wave oscillation circuits.