Efficient PWM Waveform Generation Using Rotary Encoder on Spartan-6E Starter Kit

Abstract

In this paper, an efficient pulse width modulation (PWM) waveform generator with variable frequency and duty cycle is designed and implemented. An ISIM simulator from Xilinx is used to verify the simulation, and the reference clock and system clock required to generate the PWM waveforms are based on a rotary encoder signal and an oscillator on Spartan-6E FPGA Starter Kit. A starter kit is used to implement the logic proposed in this paper. The logic configuration is designed so that the duty cycle of the PWM waveform can be changed from 0% to 100% and there are no problems in PWM waveform generation even if the rotary encoder pulse period is changed. The FPGA used to construct the application logic provides a reconfigurable architecture and is economically useful, while also providing the best flexibility to replace a microcontroller.