Functional description

ST1S41

10/27

DocID023654 Rev 2

Equation 3

where:

Equation 4

harmonic oscillations at duty cycle over 50%.

Equation 5

where:

Equation 6

and

Equation 7

The resistor to adjust the output voltage gives the term from output voltage to the FB pin.

Equation 8

ω

p

1

R

LOAD

C

OUT

⋅

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

m

C

1D

–

() 0.5

–

⋅

LC

OUT

f

SW

⋅⋅

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

+

=

m

C

1

S

e

S

n

------

+

=

S

e

V

pp

f

SW

⋅

=

S

n

V

IN

V

OUT

–

L

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

R

i

⋅

=

⎝

⎜

⎜

⎜

⎜

⎜

⎜

⎛

F

()

1

1

s

ω

n

Q

P

⋅

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

s

2

ω

n

2

-------

++

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

=

Q

P

1

π

m

C

1D

–

() 0.5

–

⋅

[]

⋅

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

=

ω

n

π f

SW

⋅

=

G

()

R

2

R

1

R

2

+

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

=