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Gate driver with fault detection

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kappa_am

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Hi all,
I am looking for a off the shelf gate IGBT/ MOSFET driver that detect fault and discriminate between short and open circuit fault. I searched all major distributor and looked at numerous datasheets, but I could not find one. I would be grateful if you let me know if you know one by any chance.

Thank you
 

Hi,

It's not clear which node you want to monitor: gate or IGBT/ Mosfet output?
What topology? High side, low side, half bridge, full bridge?
What PWM frequency and duty cycle range?
How fast you want it to react?

There are many possible requirements ... with different solutions...

Klaus
 

Short circuit protection by desaturation detection works perfectly for IGBT and in some cases for high voltage MOSFET. Many gate drivers with this function are available. Open circuit detection is no protection problem, but may be possible with additional circuit. Motor inverters are utilizing their output current sensors for this purpose.
 

Thank you for your comments.
The topology is not conventional six-pack 2-level. It is multilevel structure. The structure is a multilevel one. All driver have their own isolated voltage source for gate driving (no bootstrap). I have seen some gate drivers produced by Infineon, Semikron and Power Integeration majority of them have desaturation protection but non have open circuit protection. IGBT gen. 7 can withstand short circuit current around 8us, so SC protection perferabiliy react less than less that time minus a toleration. OC protection can be in ms range. I think, i should design extra circuit using optocoupler and some logic gates, if I don't find it off the shelf.
Is it good Idea? comparing output of a optocoupler which its diode side is connected to collector and emitter of the IGBT with voltage on gate. I think it is acceptable in range of ms. isn't it?

Thank you.
 

Do you mean open circuit detection...? if a device goes open ckt - i.e. not closed on gate drive command - then this is a fault - but a not a catastrophic fault to other devices - we do a GD board with > 10,000V / uS common mode rejection and up to 800V bus - you might like our design - what is the max freq you need? Regards EP.
 

our DC link is about 1kV (rectified 575Vac), however since it is multilevel configuration voltage on each switch is 500V. Bootstrap configuration is nit possible.
 

Hello, we have a GD system which controls up to 9 devices, all with a 100kHz 15V ac supply - all isolated ( 1500VDC working ) - which is converted to +15 & -5V on the GD boards, opto isolated GD signals, allowing a 0% & 100% on time ( i.e. indefinite ON time) all with >10kV/uS common mode, and propagation delay of 100nS max for ON command and 80nS max for OFF command. Ron and Roff selectable by user - desat detect fed back via opto coupler on each GD board ( open ckt would look like a desat ) allowing for overall controller to count de-sats and either turn whole system off at first de-sat - or count de-sats and stop system at some count number ...
 

Does it discriminate between open circuit and short circuit? can I have datasheet?
 

We don't have a formal datasheet - but no - there is no extant discrimination between a genuine desat ( overcurrent at turn on ) and device open ckt ( high volts on Collector - looks similar to de-sat ) we would need to add another high speed comparator ckt to determine whether the collector is < 10V say, compared to > 100V say ...

- - - Updated - - -

what sort of volumes would your company be interested in?
 

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