Introduction

(Circuit Specification)

For our PC 300/319 combinational project, we chose to do the Triac Demonstrator Circuit. Essentially, the objective was to design and construct a circuit that would demonstrate the triac in both Burst Mode and Delayed Trigger Mode. In addition, the circuit would include a single set of controls for duty cycle (capable of going from 0% -> 100%), and a switch for mode.

There is a 4-bit input provided by the debugger board to control the duty cycle.  With these 4 bits, there are 16 possible combinations, so we assigned 0% duty cycle to the 0000 combination, and 100% duty cycle to the 1111 combination.  All the values in the middle were assigned values appropriately.  In addition, there is also a 1-bit input provided by the debugger board that will allow us to change between delayed trigger mode and burst mode.

In terms of outputs, we will use a lamp for the physical output which will brighten, dim, and flicker on and off as required.  In addition, there will also be two outputs running to channels 1 and 2 of the oscilloscope.  Here, we can observe the behaviour of the output waveform relative to the input waveform.