The easy to be integrated chaotic frequency modulation circuit for class-D amplifier was proposed to solve electromagnetic interference(EMI) issue. In the circuit, an improved chaotic sequence generator was designed and its chaotic behavior was modeled by stroboscopic map. The proposed circuit only replaced fixed frequency ramp generator in conventional class-D amplifier architecture. Therefore, the spread spectrum triangular wave modulated by chaotic sequence was employed as carrier wave of pulse width modulation(PWM), instead of fixed frequency triangular wave. The circuit was designed, verified and implemented using 0.35μm CMOS process. Simulation results show that the peak power reduction can achieve to 15dB.
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