Protection circuit for IR2110 Class D Mosfet Driver ?

[NMOS]

Hello,

does somebody have idea,..how to protect 2 Mosfets IRFP250N and IR2110 (Class D output stage) if short circuit happenend ?

Rail is about +/- 85 V DC

have see shunt resistor in positive and negative rail as current sensing...any other working ! effective ideas with low component count

other designs have only shunt resistor in positive as current sensing

[Dzony988]

Sunt in positive or negative rail for curent sens is not good idea because you use low rds fets and output inductor and with adding a shunt you all srew up because for optocoupler or other things you need 1-1.5V drop on positive rail, this menas you add more resistion on your low rds fets and output inductor. If you have any idea post here..

[kubeek]

Current transformer like this, run a wire from the output transistors to the filter through it. Then some rectification and comparator. The type has to be suitable for the switching frequency.

[NMOS]

Originally Posted by kubeek

Current transformer like this, run a wire from the output transistors to the filter through it. Then some rectification and comparator. The type has to be suitable for the switching frequency.

Hi do you have schematic for this solution ?

Phillips using in UCD reference design...and IRF shunt resistors too.

Crest using in Half Bridge Class D Amplifier with (IR 2110 IC and APT Mosfets) shunt resistors for current sensing too

regards

[kubeek]

here, from TR3 to IC6A. Event though this is a PSU, the protection can also be used in class-d output stages.