Automatic Integrator Control with time delay IC/oscillator

[AQUAMAN]

Hello

I have a basic opamp integrator circuit. The integrator is quite fast, it integrates over a period of around 300-500nS. I have an SPDT switch that either sets the input to ground or the voltage I want to integrate

At the moment I control it from a DSP through an optical fibre terminals. However I want to somehow remove these terminals and the need for these terminals and the extra control signal from the DSP. So basically I want to make the integration control automated. I wonder if this is possible with some sort of time delay IC like a 555 timer (I dont think a 555 will work though)

In the larger circuit I already have a variety of control signals that I could trigger off. You can see the timings I have in the photo I attach. So Vg is turned off, a delay of 200nS occurs, then I integrate for 350nS (or a similar period), then stop.

What I would like to do is build a circuit that replaces the IR terminals that I have now with some sort of delay IC that is capable of reproducing the same timings shown. I would somehow trigger it off the falling of Vg.

Does anyone have any suggestions?