A mixed-signal integrator, having an analog input and a digital output, is adapted to perform an integration operation partially in the analog domain and partially in the digital domain while eliminating the limitations of a conventional analog integrator. The first frame section extends substantially vertically. 1, where is the full width at half maximum of the gain spectrum of the active layer and E is an amount of shift of an energy corresponding to the Bragg wavelength g from the center wavelength energy of the gain spectrum. This Abstract is not intended to define the invention disclosed in the specification, nor intended to limit the scope of the invention in any way.