Yes, it's true that in that case sample-and-hold is the same as a delay time. But I think we are both on the wrong track.
Within the 5ms, the X-signal could change and be back at the same voltage level as at 0ms.
Example:
0ms > 3.36V
1ms > 3.36V
2ms > 3.36V
3ms > 4.00V
4ms > 4.00V
5ms > 3.36V
In this case the signal is at 0ms the same as at 5ms.
Our safecircuit would than shut off the laser, which is wrong, because the signal has changed witin that 5ms.
So, we can not use sample-and-hold or a delay function at all
Our circuit has to be reset every time the signal has changed.
In the example above it has to 'count' from the beginning at 3ms, because here the signal has changed from 3.36V to 4.00V.
Please tell me if I'm wrong about this.
I'm having my period this week, so I can not think very clearly right now.
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