Installation and Operation

 2015 Microchip Technology Inc.

DS50002363A-page 17

of the triangular wave. Considering the maximum voltage of the triangular waves

the threshold voltages can be calculated by means of the following equation:

EQUATION 2-3:

TRIANGULAR WAVE AMPLITUDE SWING

For the MCP1664 LED Driver Evaluation Board, the components were chosen so that

they feature a PWM Dimming frequency of 125 Hz and an amplitude swing from

FIGURE 2-5:

Obtaining the Dimming Signal - 84% Duty Cycle.

VTH VTL

–

R4

R2

------VDD

=

REFERENCE

VOLTAGE

DIMMING

SIGNAL

TRIANGULAR

WAVE