Apparatus and methods of providing digital varying output, such as sinusoidal, pulse width modulation, SPWM, control for an inverter comprising at least a first switch and a second switch are disclosed. The method comprising: generating a first binary control signal at a system modulation frequency; generating a second binary control signal at an M-times higher carrier frequency; wherein generating the second binary control signal comprises: providing a periodic counter having a K-times higher reset frequency; calculating M switch-off moments; determining for each, a corresponding switch-off counter value and a corresponding counter sequence value; storing each switch-off counter value in a respective memory location corresponding to the respective counter sequence and dummy values in the remaining memory locations; and sequentially and periodically transferring the contents of the memory locations to at least one PWM value register.