Other Parts Discussed in Thread: CSD19532KTT
Dear Specislists,
My customer has a question about equation(9) of datasheet P.21.
I would be grateful if you could advise.
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I'd like to know about calculation method of RθJC
RθCA is used in equation (9) of data sheet P.21.
In Equation (10), 30 ° C./W is used for RθCA.
I don't know if it's CSD19532KTT or CSD17552Q5B, (but I think either is a typo.)
RθCA is not described.
From each data sheet, subtract RJC from RθJA.
CSD19532KTT: 62 ℃ / W-0.6 ℃ / W = 61.4 ℃ / W
CSD17552Q5B: 50 ℃ / W-1.8 ℃ / W = 48.2 ℃ / W
In either case, it is not 30 ° C / W.
How was it calculated?
On the other hand, the Excel calculation tool uses θJA.
Here, TI EVM is listed as The EVM is 30 ° C / W number and a good starting point at 30 ° C / W.
In the data sheet, is the initial value of RθCA set to a typical value of 30 ° C / W for RθJA of EVM?
(In this case, RθJA and RθJC are different, but are they ignored because RθJC is small?)
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I appreciate your great help in advance.
Best regards,
Shinichi