I'm designing a phonic wheel emulator. I have a PIC18F4550 and the following power supplies: +5V, -5V, 12V. I need to geneate a sine waves from frequencies near 500Hz up to approximately 8kHz. The shape does not need to be a perfect sine, but the amplitude needs to be at least 10V or higher for all frequencies.
The controlling of the frequencies can be made manually or digittaly (it means the person can vary the frequency using a potentiometer or typing the frequency on the device)
I thought to generate a square wave by the microcontroller and use a active filter to filter the high order harmonics, but I think this is not a good approach because the frequency band is relativelly wide. I heard about sine lookup table and DAC, but PIC18F does not have DAC module.
I read about LTC1066-1 at the best answer chosen to this question. But I didn't understand very well, it seems to use a PLL and a LTC1066, it seemed a bit expensive and complex to me.
Another approach is one that I found here. But it sems to be even worse because it does not have a explanation of the signals required only a electrical scheme with some signal inputs that I don't know from where it come from.
Is there a simpler and non expensive way of reach this purpose ? Does someone have any suggestion ?