Here is the block diagram for the PWM14 D/A. A key component is a counter with the desired resolution, in this case 14-bits. There is also a register with the same bit width as the counter. It holds the desired duty cycle/compare value. Since the PWM14 has two channels, there are two registers. Two comparators (with the same bit width as the counter) detect when the counter reaches the desired value. Some basic control logic is included, of course. There is also a clock select circuit. This is not really required, but it adds some design flexibility to the PWM14. The Module Stop signal that connects into the PWM14 module causes it to cease operation and puts it back to the reset defaults. If the customer stops the PWM14 to save power, they will need to re-initialize this peripheral when they want to use it again. It should be pointed out here that when the MCU is forced to go into one of its power-saving modes (Module Stop, Hardware Standby or Software Standby), the PWM14 D/A will cease to generate pulses on its output. If this is a problem, one solution is to use a Sample-and-Hold circuit on the analog side of the filter.