STEVAL-ISV009V1 STMicroelectronics, STEVAL-ISV009V1 Datasheet - Page 37

• Manufacturer Part Number: STEVAL-ISV009V1
• Description: Power Management Modules & Development Tools DUAL STG DC/AC CNVRT DEMO BRD
• Manufacturer: STMicroelectronics
• Series: -r

Specifications of STEVAL-ISV009V1

• Design Resources: STEVAL-ISV009V1 BOM STEVAL-ISV009V1 Schematic
• Main Purpose: DC/DC, Step Up
• Outputs And Type: 1, Non-Isolated
• Power - Output: -
• Voltage - Output: 36V
• Current - Output: -
• Voltage - Input: -
• Regulator Topology: Boost
• Frequency - Switching: -
• Board Type: Fully Populated
• Utilized Ic / Part: SPV1020
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AN3392
13.13
13.14
D3 has to be chosen taking care mainly to its low forward voltage in order to impact as less
as possible the system efficiency. Maximum forward current will be according to the
maximum current sink by SPV1020: a safe choice is around 20 mA. Maximum voltage
applied to D3 depends on the PV panel, and anyway can’t be > 40 V, due to the technology
constraints of SPV1020.
D1 is the alternative path to the current flow when SPV1020 is down and Vin voltage level is
higher than Vout.
D2 acts as a typical by-pass diode: it turns on in case of shaded cells and provides an
alternative path to the current flowing from other panels.
D1 and D2 are power schottky diodes that must support both:
●
●
Furthermore forward voltage and reverse current of D1 and D2 should be lower as possible
in order to impact as less as possible the system efficiency.
Protection devices
SPV1020 demo board mounts a protection transil D4 to avoid the output voltage triggers
spikes higher than the safety threshold of 40 V.
This component has to be choice according to the following rules:
VBR > Vout_max;
and
VCL
For ISV009v1 mounts D4 which has VBR = 37 V and VCL = 40 V.
Pole-zero compensation
SPV1020 controls of the whole system stability by an internal loop on Vout_sns.
Transfer function of the loop depends on both output capacitor and load.
Even if the stability can be fine tuned by trimming R5 and C8, their suggested values (R5 =
1 kΩ and C8 = 22 nF) guarantee stability in most applications.
In order to speed-up the system reaction to output voltage changes causing the Over
Voltage threshold triggering, C8 can be decreased up to 2.2 nF.
Forward current comparable with the maximum current provided by the PV cells.
Assuming a PV panel with 6” poly crystalline silicon solar cells, then maximum current
will be 9 A.
Maximum reverse voltage according to the output voltage partitioning. So, at least 40 V,
due to the technology constraint of SPV1020.
≤
40 V.
Doc ID XXXXX Rev 1
External component selection
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