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[alexychen96]

high side switch

I want to design a high side switch which uses IR2125. IR2125 is used to drive a N-Channel Power MOSFET.But i was confuse by the MOSFET in the datasheet of IR2125. The MOSFET has 4 pins. I usually use MOSFET such as IRFP250. It has only 3 pins. Could any one do me a favor and tell me what kind of MOSFET should I choose in this case. The feasure of MOSFET is like IRFP250.

the attachment is the datasheet of IR2125

Thanks

 

[nicleo]

irf2125

The 'CS' pin of IRF2125 is the current sense input to current sense comparator. The mosfet used in the datasheet has 4 pins, and one of them is connected to the CS pin to protect the mosfet from overcurrent.

International Rectifier offers few mosfets that feature integrated programmable over-current protection, e.g. IR3310, IR3311, and IR3312 ( http://www.irf.com/product-info/auto/autoir331x.html ). This family of mosfet has 4 pin.

You may wish to read the following articles:

Using The Current Sensing IR212X Gate Drive ICs
http://www.irf.com/technical-info/appnotes/an-1014.pdf

Programmable High Side Current Switch IR3310/11/12
http://www.irf.com/technical-info/appnotes/an-1058.pdf

 

[devura]

programmable current sensing high side switch

Hi nicleo,

Could you pls help me out

I am using the same circuit as described above. I am finding it difficult to protect the IGBT from short circuit. My IGBT as well as the IR2125 are going bad.

Give me a solution