Design equations for the modified buck converter

AN2928

18/21

Winding resistance depends on the diameter, and is defined using the following formula:

Equation 45

R = wire resistance (

Ω)

p = resistivity of the copper (

Ω

l = wire length (cm)

d = wire diameter (cm)

The wire diameter is properly selected if the total wire resistance is lower than the maximum

wire resistance.

Equation 46

Rp

l

S

----

p

I

N

N

⋅

π d

⋅

----------------

⋅

=

⋅

=

RR

MAX WIRE

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