STMicroelectronics STLDC08 Demo Board STEVAL-ILL039V1/2 STEVAL-ILL039V2 STEVAL-ILL039V2 Fiche De Données
Codes de produits
STEVAL-ILL039V2
Application information
STLDC08
18/29
Doc ID 18476 Rev 1
Equation 6
Where D
MAX
is given by:
Equation 7
The value of the peak current on the inductor is given by the following equation:
Equation 8
The minimum required saturation current of the inductor must be greater than I
L(PK)
and can
be expressed as follows:
Equation 9
The saturation current rating for the inductor should be checked at the maximum duty cycle
and maximum output current.
and maximum output current.
8.4
Inductor peak current limit
The value of the inductor peak current limit can be programmed either by using a sense
resistor or by using the RDSON of the main Power MOSFET.
resistor or by using the RDSON of the main Power MOSFET.
The following equation gives the relationship between the peak current limit and the value of
the sense resistor:
the sense resistor:
Equation 10
The sense resistor value can be determined fixing the value of the inductor peak current
limit equal to twice the value of the inductor peak current in steady-state conditions.
limit equal to twice the value of the inductor peak current in steady-state conditions.
MAX
LED
)
AVG
(
L
L
D
1
I
%
40
I
%
40
I
−
×
=
×
=
Δ
D
OUT
)
MIN
(
IN
MAX
V
V
V
1
D
+
−
=
2
I
I
I
L
)
AVG
(
L
)
PK
(
L
Δ
+
=
2
I
D
1
I
I
I
L
MAX
OUT
)
PK
(
L
)
SAT
(
L
Δ
+
−
=
>
SENSE
SENSE
SENSE
)
MAX
(
IN
R
1
.
0
R
V
I
=
=