AN2928

Design equations for the modified buck converter

9/21

inverse can be calculated with Equation 15.

Equation 14

Equation 15

note AN1792. See Section 3: Reference and related materials).

Equation 16

following equation:

Equation 17

R

4

t

OFF

2.1

C

4

⋅

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

=

C

4

t

OFF

2.1

R

4

⋅

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

=

V

GD MAX

V

ZCD C LAMP

–

V

F

–

l

ZCD M AX

V

ZCD C LAMP

R

4

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

+

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

R

5

R

4

V

GD MIN

V

ZC D CLAMP

–

V

F

–

V

ZCD CL AM P

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

⎝⎠

⎜⎟

⎜⎟

⎛⎞

⋅

<<

C

3

C

4

V

ZCD CL AM P

V

GD M AX

V

ZCD C LAMP

–

V

F

–

()

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

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