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Thermal Resistance of AD9523 -calculate an external heat sink

Question asked by Kou on Jun 3, 2011
Latest reply on Jun 3, 2011 by MFelmlee

HI.

 

I have a question about AD9523 Clock Generator.

 

Which of Ψjt or θjc should I use when an external heat sink is needed?.

 

*An external heat sink is attached on upside of device.

*Also, an exposed pad is connected with PCB-layer correctly.

 

Data sheet describes about thermal considerations. below,

The value of Ψjt and θjc has a big difference.

 

It would be greatly appreciated if advice could be gotten.

 

Best Regards,

 

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