STEVAL-ISV008V1 STMicroelectronics, STEVAL-ISV008V1 Datasheet - Page 9

• Manufacturer Part Number: STEVAL-ISV008V1
• Description: IC LINEAR
• Manufacturer: STMicroelectronics
• Series: -r

Specifications of STEVAL-ISV008V1

• Design Resources: STEVAL-ISV008V1 Schematic STEVAL-ISV008V1 BOM
• Main Purpose: Special Purpose DC/DC, Photovoltaic
• Outputs And Type: 3, Isolated
• Power - Output: 300W
• Voltage - Output: -
• Current - Output: -
• Voltage - Input: 0 ~ 40 V
• Regulator Topology: Boost
• Frequency - Switching: 100kHz
• Board Type: Fully Populated
• Utilized Ic / Part: SPV1020
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-11419

SPV1020
5.2
5.3
Note:
Oscillator
The switching frequency is internally fixed at 100 kHz and each phase works at the
frequency fixed by the oscillator. If the user wants to set the default value, the OSC pin has
to be tied to VREG. Otherwise, the switching frequency can be fine tuned in the range from
50 kHz to 200 kHz by connecting an external resistor between OSC pin and SGND. Related
formula is reported below.
Input voltage sensing
The device monitors through VIN_SNS pin the input voltage generated by the PV cells
string; this value is used to calculate the power generated by the PV cells string and then to
tune the PWM accordingly to the maximum power point.
Input voltage must be scaled to the reference voltage level (1.25 V) of the ADC integrated in
the SPV1020.
Referring to the schematic showed in Application circuit, R1 and R2 are the 2 resistors used
for partitioning the input voltage.
Said VIN_MAX the maximum input voltage of the supply source (e.g. the PV panel or the PV
string), R1 and R2 must be selected according to the following rule:
Also, in order to optimize the efficiency of the whole system, when selecting R1 and R2,
their power dissipation has to be taken into account.
Assuming negligible the current flowing through pin Vin_sns, maximum power dissipation on
the series R1+R2 is:
As empiric rule, R1 and R2 should be selected according to:
In order to guarantee the proper functionality of pin V
R1+R2 should be in the range between 20 µA and 200 µA.
P
Doc ID 17588 Rev 2
vin
_
sns
R
P
6
vin
k [
R
<<
R
Ω
_
2
1
.
]
sns
01
=
=
x
Fswitch
=
V
(
V (
100
. 1
in
V (
in
_
R
25
)
in
max
_
1
×
max
_
+
(
120
max
k [
R
Hz
2
in_sns
)
)
I
2
in
]
_
max
current flowing on the series
)
Detailed description
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