I would like to open and close a shutter (acousto-optic modulator) really fast. Really fast in this case means 2 MHz. However, the shutter should not be modulated periodically, e.g. with constant frequency. The shutter shall open, when an analog input signal Uin is above a certain threshold U1 and close again above another threshold U2.
Furthermore, the voltages U1 and U2 are provided digitally as 16 bit numbers. Both are not static, however. They will change in the worst case with a frequency of 1 MHz.
An added bonus would be, if the actual level of Uout does not have to be binary but could also be modulated with 1 MHz.
I tried to sketch a schematic for this:
So obviously I thought to solve this problem using either a window-comparator or a FPGA. The latter one would give me more flexibility on future changes. Looking a bit on the National Instruments website, I did not find a fast enough FPGA (actually the DA/AD outputs/inputs are not fast enough).
The problem itself seems very basic to me. Am I overlooking an obvious implementation?