circuit provide 500 V DC pulse

jiripolivka said:

You need first a DC source with 500 V output. For an "extremely low current" you can use a capacitor charged to 500 V.

From 120V AC, I would use a voltage tripler or a 120V/450V transformer and rectifier diodes rated to ~1 kV.

As "the push button" must not be in the 500 V circuit", you can use a relay to transfer the 500V from the charged capacitor to the load. You can also use a SCR or a thyristor for the purpose, or a HV MOSFET.

As there is no definition of the output pulse shape, no more details can be invented. Also the load must be well defined.

Please be aware that anything connected to 120V AC and generating 500V can be extremely dangerous; people can be killed by it.

I your teacher gave you such task, such person looks to me very uneducated; be careful of such wrong definitions.

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jatnc said:

Thank you for your help. The 500 V Dc pulse is required ignition coil in order to ignite the gas inside of a flash lamp that is used to optically pump a alexandrite laser. Could you provide me the circuit diagram with the components, please?
Thanks in advance...

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jiripolivka said:

I think 500 V pulse specification may not work. I used >3 kV to trigger a photo flash tube. The best advice is to try photoflash circuits used in single-use cheap cameras . They operate on 3 V DC.. If more voltage is needed, try to look on "www.allelectronics.com", they sell 12 VDC photoflash light circuits you can use. THe cost is ~$6 , easier than building your circuit.
If the repeat frequency should be higher than 1-2 Hz, use a car ignition coil driven from 12 VDC by a 2N3055 transistor or IRF 520 MOSFET.The driving pulse generator is a 555 IC. Lots of HV pulse circuits can be found on the Eda board forum. You can try also a low-cost electric fence pulse source.

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jiripolivka said:

I have built several similar circuits, mainly to fire the photoflash lamp with A rate of >10 Hz. I did it 35 years ago, so I have no schematics to offer. Please try the "www.allelectronics.com", they sell such kits for $6 or so, with a photoflash lamp included.
You can try if the circuit can fire your lamp. The trigger pulse transformer is the secret; you can make yours with a "longer" secondary if >3 kV is needed. This transformer must be located close to the triggered lamp, other components can be far from it.

A chopper interrupting a DC voltage does not generate "DC pulses" but rectangular ones. A "simmer" power supply means that it generates a much lower current than normal.

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