Patent ID: 8872581

Claim:
A triangular wave generator for generating a variable frequency triangular wave, the triangular wave generator comprising: a variable current source module for receiving a plurality of control signals to adjust an output current of the variable current source module, the variable current source module comprising a plurality of variable current source units, and each variable current source unit provides a variable current to the output current of the variable current source module, each variable current source unit comprising: a fixed current source circuit for providing a fixed current to the output current of the variable current source module; and a plurality of fine-tune current circuits coupled to the fixed current source circuit for providing a plurality of fine-tune currents to the output current of the variable current source module, wherein the plurality of fine-tune current circuits adjust the plurality of fine-tune currents through the plurality of control signals; an energy storage module coupled to the variable current source module for receiving the output current of the variable current source module to maintain a storage voltage; a comparison module coupled to the energy storage module for comparing the storage voltage, a high reference voltage, and a low reference voltage to generate a plurality of comparison signals; and a control module coupled between the comparison module and the variable current source module for receiving the plurality of comparison signals, and generating the plurality of control signals to adjust the output current of the variable current source module; wherein a frequency of the variable frequency triangular wave is changed with the output current of the variable current source module.