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LM2940C: LM2940T schematic double check

Zhihong Huang
Intellectual 1550 points
Part Number: LM2940C

Hi team

Could you please help me double check this schematic?

Best Regards,

Wesley Huang

Email: wesley-huang@ti.com

  • 0
    TI__Mastermind 44770 points

    Hi Wesly,

    Just curious as to the purpose of R84.

    Thermally, the above schematic shows (18-12)*0.35 or 2.1W of power dissipation. This might be OK in the TO-220 package, but would be very marginal if you are using the SOT-223 package. 

    TO-220 : 2.1W*23.3C/W= 48.9C rise above PCB ambient

    SOT-223 : 2.1W*59.3C/W= 124.5C rise above PCB ambient.

    I hope this helps.