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Exposed Pad of AD5421

Hello,

I am working on laying out the AD5421 TSSOP-28 package.  I have been using the evaluation board for testing and want to replicate that design as much as possible. 

When looking at the AD5421 evaluation board user guide (UG-250), Figure 7 shows the how designer laid the AD5421.  I am attaching a snippet of this below:

According to the data sheet (page 13), the exposed pad "should be connected to the same potential as the COM pin and to a copper plane for optimum thermal performance."  The layout on the evaluation board agrees with this.  It is connected to the same potential as COM pins (pin 13 and 14).  It is also connected to a copper plane. 

My question is, how can this be soldered with such as large copper plane?  I would expect the exposed pad to have spokes to a copper plane to allow it to be soldered, but still be connected to the copper plane, much like how the MOSFET on the evaluation board is laid out.  See below:

As a said, I want to replicate this design as much as possible, because of the good performance.  I would prefer to use thermal spokes to connect the AD5421 exposed pad to a copper plane, because I know this will solder more easily, but I don't want to effect the performance.  So which layout is preferable; exposed pad connected to copper plane with thermal spokes, or just fully connected? 

Please let me know if you have questions.  I appreciate any suggestions or advice on this.

-SC