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I am using some UV-C LEDs in a design, and as these emit dangerous radiation, I am looking for a circuit that will rapidly blow the diodes if access is gained. It would need to retain sufficient energy for a few weeks after any power is removed, but needs to be a small as possible. The plan would be to destroy them if: - Power is removed for more than a week (after the unit having been first used) - Stored energy is dropping below a threshold that ensures destruction - Access is detected I am thinking capacitive discharge, but any comments appreciated on other approaches!

There are many possibilities. One of them is to fill the box, air tight, with extra pressure and if a hole is made, the pressure drop, and an internal membrane may detect it. As far what it could do, I could try to erase the code of the MCU, when the pressure drop occurs, as example, rather than bombing or electrocuting the circuit, since I could then re-load the program if it was just a mistake. Because I would try to use an MCU, such as the MSP432 from TI, which can go into a sleep mode drawing few micro-amps, in quiescent mode, even in the nano-amp range, and which can easily wake up from an external signal, such as a raising edge of voltage. Back to the membrane, either it is piezo electric (so its movement generates the electrical pulse which will awake the MCU), either it closes a loop implying a charged capacitor which will then try to discharge itself when the electrical loop is completed (a capacitor holds its charge when NOT part of a loop, but an internal resistance is a leak to each and every cap. Just need a cap which has a very low leakage). I repeat, that is just ONE of MANY possible scenario. But overall, try to have one which can handle and gently recover from honest human mistake, if possible.