cancel
Showing results for 
Search instead for 
Did you mean: 

High Voltage Pulse Discharge

OKula.1
Associate

I would like to discharge my capacitor at high voltage(1200V). The load will reach 1000 A about 150-200 ns, and ring down. In order to switch that capacitor, i need high di/dt switching device. SCT50N120's diode is fast enough for my application, but its datasheet does not include the information about di/dt rate of the mosfet. What is di/dt rate of the mosfet? Is SCT50N120 suitable for my application? The attachment can give you a clue about my goal. Thank you.

3 REPLIES 3
Ozone
Lead II

If that property is not specified in the datasheet, you might need to approach ST directly.

I suppose you will have a hard time finding an appropriate MOSFET. I learned of di/dt related fails of device in one of my former companies, with rise times in the microsecond range.

AFAIK, many capacitors do not like short-circuiting either. The high current exerts large internal forces, which will tear up the device in a short time.

OKula.1
Associate

Thank you for your answer. Do you think this device can handle the 1000 A current? I mean maximum drain pulse current is 130A, but i apply 1000A about 100 nanosecond. My question is not specific for this device. Generally, switching devices have limited max current value for a couple of seconds or miliseconds, so i can't find a device for my application.

I just have the hardware knowledge I picked up along the way as SW developer.

As stated, I would suggest to contact ST or a distributor. They should be able to recommend you a device.

Datasheets use to specify continuous current loads and pulse loads (including a SOA), but not down to your level.

AFAIK, thyristors and triacs have no inherent forward di/dt problems like MOSFETs.

Or parallel banks with power BJTs.