There are several ways.
>Output a 2khz square wave. Pass it through a serious 2khz low-pass filter. The filter will remove all the harmonics above 2khz leaving a sinewave.
>I do not know the ARM7 well. Make the PWM run at 200khz which is 100x what you want. Use a 100 point sine lookup table. Each time the PWM (timer) overflows reload the timer with the next number in the table. The output of the PWM will need a lowpass filter but the filter can be as fast as 100khz.
I hope you know a 100 point table can be made using only 25 points.