DPWM modulator using VLSI

The rapid progress in motor control and microelectronics has made the
universal dc drives a major field of interest. Traditionally most of these applications
today adopt either analog or microprocessor based PWM control schemes. The
disadvantages possessed by these schemes are complex circuitry, limited functions
and difficulty in circuit modifications.
Due to the advances in the digital technology, digital pulse width modulated
convertors are becoming more popular in dc motor drive and also in dc power
conditioning applications. The development in the digital signal processors has
encouraged the digital PWM control. The advantages of the digital signal processors
based control schemes are simple circuitry, software control and flexibility. However
generating PWM signals require high sampling rate to achieve a wide band width
performance. Another disadvantages is that longer time is required to develop the
software in a new processor structure and moreover, processor controlled by software
is not suitable for a switching circuit, which generating lot of noise, resulting in high
risk of collapse.
Dynamic and ever progressing change in very large scale integration technology
(VLSI) has radically affected the design process cheap, reliable and less time
consuming. More over the fpga based design is also more reliable than the
microprocessor based system because they do not need any control software.
Dpwm ac-dc converter serves wide range of applications and also plays an
important role in the minimization of harmonics and switching losses in the
converter circuits. In the past two decades various pwm strategies, control schemes
and realization techniques have been developed. These pwm strategies were realized
either by analog or microprocessor based software control techniques. This project
proposes a novel realization scheme for dpwm ic using VLSI which may serve as the
switching circuit for the ac-dc converters.

Driver circuit and DPWM converter are initially tested on a breadboard. Later
they are fabricated using a printed circuit board (PCB