SPV1050 datasheet(17/36 Pages) STMICROELECTRONICS

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SPV1050

Functional description

Figure 5

shows the behavior of input voltage VIN and VSTORE at the startup.

Figure 5. Boost startup

In the range 2.6 V

 VSTORE < VEOC the voltage is boosted by the DC-DC converter. In this

voltage range the SPV1050 device sets its internal impedance according to the integrated

MPPT algorithm (the MPPT mode is active). The SPV1050 device will stop switching for

400 ms (TSAMPLE) every 16 seconds (TTRACKING). During the TSAMPLE, the input open

circuit voltage VOC is sampled by charging the capacitor on the MPP-REF pin. Once the

TSAMPLE is elapsed, the DC-DC converter will start switching back by setting its own

impedance such that VIN stays as close as possible to VMPP of the source. A resistor

partitioning connected between the source and the pins MPP and MPP-SET has to be

properly selected, in order to match the manufacturer's specs. Please refer to Section 6.4:

MPPT setting on page 24

for further details.

The periodic sampling of VOC guarantees the best MPPT in case of source condition

variations (e.g. irradiation/thermal gradient and/or temperature changes).

SPV1050 数据表(PDF) 17 Page - STMicroelectronics