SPV1040 operating description

AN4123

4/17

DocID023264 Rev 2

The MPPT algorithm sets up the DC working point properly by guaranteeing Z

IN

= Z

M

(assuming Z

M

the impedance of the supply source). In this way, the power extracted from

the supply source (P

IN

= V

IN

x I

IN

) is maximum (P

M

= V

M

x I

M

).

The voltage current curve shows all the available working points of the PV panel at a given

solar irradiation. The voltage power curve is derived from the voltage current curve by

plotting the product V x I for each voltage generated. For further details on the MPPT

algorithm, please refer to the SPV1040 device datasheet.

Figure 4. MPPT working principle

Figure 5. SPV1040 internal block diagram

AM11736v2

Lx

START SIGNAL

ZERO CROSSING

+

ANALOG BLOCK

START SIGNAL

VREF

+

-

ZERO CROSSING

DETECTOR

XSHUT

-

OVERCURRENT

OVERTEMPERATURE

REVERSE POLARITY

MPP-SET

+

-

MPP-SET

MPP BLOCK

CLOCK

BURST MODE

DAC CODE

DIGITAL

CORE

PWM

GND

+

-

VREF

IOUT Reg.

VIN Reg.

-

VOUT Reg.