Generation of multiple frequency pulse width modulation signals using FPGA

Abstract EN

Microcontrollers, such as the ones used in Arduino, are low-cost, simple, and suitable for low frequency and speed applications.

However, concurrent processing and concurrent generation of multiple signals are necessary for many applications such as the automotive sector, broadcasting, consumer electronics, and industrial applications.

Field Programmable Gate Arrays (FPGAs) can generate concurrent signals that are more accurate than signals generated by microcontrollers.

Moreover, FPGAs have higher performance than microcontrollers do, mainly in high-frequency applications.

In this paper, multiple frequency pulse width modulation (PWM) signals are concurrently generated from an FPGA Cyclone IV core board.

The frequency of the generated PWM signals, the duty cycle, and the bit resolution is reconfigurable via simple variables in the entity section.

The solution consists of six PWM signals.

The generated signals are employed in three practical scenarios.

In the first scenario, three of the produced signals are used to control light-emitting diodes (LEDs) and generate music tones and alarms.

In the second scenario, one of the produced PWM signals is used to generate a sine wave and then smoothed via an add-on filter, making the developed system work as a function generator.

In the third scenario, one of the produced PWM signals is used to control the speed of a motor by changing the duty cycle percentage.

In this context, the developed system works as an analog to digital converter (DAC) that is able to control analog systems from a digital environment.

The proposed system is compact, low-cost, scalable, and generates accurate signals.