Design of a Linear Triangular Waveform Generator in Class D Audio Power Amplifier

A CMOS current-controlled linear triangular waveform Generator for class D amplifier application is presented, in which constant-current sources generated from VDD /2 reference voltage are used to charge and discharge the capacitor. Theoretical derivation and spectre simulations show that, the oscillation frequency is supply-independent and the waveform peak-to-peak value is direct proportional to supply voltage, junction temperature insensitive and process deviation insensitive. The proposed circuit is realized in CSMC 0.5μm 5V twin well twin poly CMOS process, and test results show that the triangular wave is well stable and linear.