APEC 2007 Session T8: Semiconductor Devices

Slide# 8

State-Machine State-Change Limits, continued

•

Power Delivery in DCM versus CCM

the inductor current perturbation,

, must be taken into account. Thus, the

inductor current,

, at the end of the cycle following the skipped cycle is

and the power delivered in a train of m CCM switching cycles in time

(m+1)Ts following a perturbation,

, would thus be

s

LIMIT

DCM

O

f

LI

P

2

,

2

1

=

)]

2

1

)(

||

(

)[

||

(

)

2

)(

(

)

2

(

)

1

(

min

min

,

s

IN

L

O

LIMIT

IN

L

O

LIMIT

O

IN

L

IN

O

LIMIT

L

O

O

O

CCM

O

Lf

V

n

V

I

V

n

V

I

I

V

V

n

V

V

I

I

n

D

V

I

V

P

−

=

+

+

=

+

−

=

=

^

)

0

(

L

i

)

(

min

i

I

p

−

i

in

L

o

L

IN

L

O

s

LIMIT

i

in

L

o

L

p

V

n

V

i

V

n

V

L

T

I

V

n

V

i

I

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)

(

)

0

(

)

||

(

)

(

)

0

(

)

(

^

^

min

min

−

+

−

=

−

+

=

−

^

)

0

(

L

i

]

)

)

(

)

0

(

)

||

(

(

[

)

1

(

2

))

(

(

)

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2

2

0

^

0

1

2

2

min

1

2

,

i

IN

L

L

IN

L

s

m

i

LIM

LIM

s

p

m

i

LIM

s

CCM

O

V

n

V

i

V

n

V

L

T

I

mI

T

m

L

i

I

I

T

m

L

P

−

+

−

−

+

=

−

+

=

∑

∑

=

−

=

(3)

(4)

(5)

(6)