MP400FCU

MP400FC

P r o d u c t I n n o v a t i o n F r o m

thermal consiDerations

For reliable operation the MP400FC will require a heatsink for most applications. When chosing the heatsink the

power dissipation in the op amp and the SMPS MOSFET switch (Q2) are both considered. The power dissipation of

the op amp is determined in the same manner as any power op amp. The power dissipation of the MOSFET switch

(Q2) is the sum of the power dissipation due to conduction and the switching power.

P

2

• R

Where:

V

IN

= SMPS input voltage

V

B

= SMPS output voltage

I

O

= total SMPS output current

FSW

= 100KHz

R

DS(ON)

= 0.621Ω

t

r

D

= T

t

2 • I

-6

•

(

)

V

F

2

I

V

t

1

V

B

V

contactinG cirrus loGic support

For all Apex Precision Power product questions and inquiries call toll free 800-546-2739 in North America. For In-

ternational customer support, contact a local Cirrus Logic Sales Representative.

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