Thermal resistance Rθ(JB)

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Hello,

I am looking for the parameter Rθ(JB) (Thermal resistance Junction - Board) for MOSFET item No. IPT65R033G7XTMA1. Is this information available somewhere please? I found only Junction - Case and Junction - Ambient.

Thank you

Adam
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1 Solution
roewetom
Employee
Employee
5 sign-ins 5 replies posted First solution authored

Hi Adam,

maybe its good to say some words about the different Rth values. The ones you find in the data sheet are basically RthJC (junction to case) and RthJA (junction to ambient). 

The RthJC reflects basically the Rth of the MOSFET it self (means MOSFET only), from the die inside to the bottom case ( in this case it is the exposed pad of the TOLL package). PCB or board is not included in this one, as it ends at the case of the MOSFET package.

The RthJA is the Rth from the die to your ambient temperature (for example the temperature inside a housing where your PCB is located), in this one the PCB is included and that is the reason why different RthJA are mentioned due to different board setups mentioned in conditions. Like you have only the footprint and nothing else or you have multiple layers and larger copper areas connected. There are also JEDEC standards which describing this setups e.g. 1s0p or 2s2p which are widely used.

If in your case you only need to know the MOSFET it self than this is the RthJC value.

I hope I could get a light into the question and it helps also other community users to better understand the given values in the data sheet.

Best regards

Tom

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1 Reply
roewetom
Employee
Employee
5 sign-ins 5 replies posted First solution authored

Hi Adam,

maybe its good to say some words about the different Rth values. The ones you find in the data sheet are basically RthJC (junction to case) and RthJA (junction to ambient). 

The RthJC reflects basically the Rth of the MOSFET it self (means MOSFET only), from the die inside to the bottom case ( in this case it is the exposed pad of the TOLL package). PCB or board is not included in this one, as it ends at the case of the MOSFET package.

The RthJA is the Rth from the die to your ambient temperature (for example the temperature inside a housing where your PCB is located), in this one the PCB is included and that is the reason why different RthJA are mentioned due to different board setups mentioned in conditions. Like you have only the footprint and nothing else or you have multiple layers and larger copper areas connected. There are also JEDEC standards which describing this setups e.g. 1s0p or 2s2p which are widely used.

If in your case you only need to know the MOSFET it self than this is the RthJC value.

I hope I could get a light into the question and it helps also other community users to better understand the given values in the data sheet.

Best regards

Tom

0 Likes