STEVAL-ISA052V2 STMicroelectronics, STEVAL-ISA052V2 Datasheet - Page 36

• Manufacturer Part Number: STEVAL-ISA052V2
• Description: BOARD EVAL BASED ON PM6675A
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of STEVAL-ISA052V2

• Design Resources: STEVAL-ISA052V2 Gerber Files STEVAL-ISA052V2 Schematic STEVAL-ISA052V2 Bill of Material
• Main Purpose: DC/DC, Step Down with LDO
• Outputs And Type: 2, Non-Isolated
• Voltage - Output: 1.5V, 0.6 ~ 3.3V
• Voltage - Input: 4.5 ~ 36 V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: PM6675AS
• Input Voltage: 4.5 V to 36 V
• Output Voltage: 1.5 V
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Power - Output: -
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Supplier Unconfirmed
• For Use With/related Products: PM6675AS
• Other names: 497-8413

Application information
36/48
With these considerations, the inductance value can be calculated with the following
expression:
Equation 30
where f
is the inductor current ripple.
Once the inductor value is determined, the inductor current ripple is then recalculated:
Equation 31
The next step is the calculation of the maximum r.m.s. inductor current:
Equation 32
The inductor must have an r.m.s. current greater than I
stability.
Then the calculation of the maximum inductor peak current follows:
Equation 33
I
The saturation current of the inductor should be greater than I
saturation core inductors. Using soft-ferrite cores it is possible (but not advisable) to push
the inductor working near its saturation current.
In
Table 11.
LPEAK
Table 11
COILTRONICS
Manufacturer
COILCRAFT
COILCRAFT
WURTH
is important in inductor selection in term of its saturation current.
SW
is the switching frequency, V
some inductors suitable for typical working conditions are listed.
Evaluated inductors (@ f
MVR1261C-112
MLC1538-102
7443552100
HC8-1R2
Series
I
∆
, L
I
RMS
, L
I
MAX
, L
PEAK
L
=
=
=
I (
IN
V
V
=
sw
LOAD
Inductance
fsw
IN
IN
I
is the input voltage, V
LOAD
,
MAX
−
= 400 kHz)
fsw
(µH)
,
∆ ⋅
1.1
1.2
MAX
V
1
1
OUT
,
MAX
I
−
L
⋅
L
)
V
2
OUT
⋅
+
+
V
V
∆
(
OUT
∆
IN
I
⋅
, L
I
L,RMS
2
, L
V
MAX
12
V
MAX
IN
current (A)
OUT
+40°C rms
,
MAX
)
13.4
16.0
in order to assure thermal
2
LPEAK
20
16
OUT
is the output voltage and
not only in case of hard
-30% saturation
current (A)
21.0
25.4
PM6675AS
20
20