Definitions

(The Modes)

In burst mode, the triac turns on at zero crossing, and stays on for the length of the duty cycle, and once the duty cycle is up, it turns off for the rest of the cycle.  Essentially, the output lamp will flicker if this mode is implemented correctly.  At a duty cycle of 0%, the lamp will be completely off, and at a duty cycle of 100%, the lamp will be completely on with no flicker. For the values of duty cycle between 0 and 100%, the light will flicker at increasing intensities.  Below is an example (light bulb) of what one would expect to see in "Burst Mode".

In delayed trigger mode, the triac must turn on quickly during the cycle.  Basically, there is a delay equal to      the full cycle minus the duty cycle where the trigger output is 0, and then the triac turns on and remains on for the rest of the cycle.  Another point that is often overlooked is that the entire delayed trigger mode cycle occurs within one cycle of burst mode, so an external clock running 16x faster (in our case) is required to implement this mode correctly.  Essentially, the output lamp will change intensities if this mode is implemented correctly.  At a duty cycle of 0%, the lamp will be completely off, and at a duty cycle of 100%, the lamp will be at it's brightest. For the values of duty cycle in between 0 and 100%, the light will get brighter as the duty cycle increases.  Below is an example (light bulb) of what one would expect to see in "Delayed Trigger Mode".