Datasheet

6.9 Undervoltage lockout
In order to prevent batteries from over-discharging, the device turns OFF in case of MPPSET voltage is lower
than 0.24 V (no irradiation). A hysteresis has been implemented to avoid unpredictable ON-OFF switching.
6.10 Reverse polarity
In order to avoid damage to the device and battery discharge when the solar panel connection is reverse-inserted,
a dedicated protection circuit has been implemented. In such condition, the SPV1040 stays OFF until the panel is
inserted correctly.
Figure 6. MPPT working principle
6.11 Burst mode
When the output voltage reaches the battery charge voltage, the MPP-SET voltage drops below 450 mV, or the
output current reaches the output maximum current limit, the duty cycle D drops down to 10% and the device
evolves from operating mode to burst mode. The converter no longer works at constant frequency, but at
frequencies gradually lower (1 T
ON
over 1 PWM cycle, 1 T
ON
over 2 PWM cycles, …,1 T
ON
over 16 PWM cycles)
prior to entering sleep-in mode.
6.12 Sleep-in mode
Once sleep-in mode has been entered, no current is provided to the load. The device exits this mode once the
cause, which forced it into this state, is no longer present.
SPV1040
Undervoltage lockout
DS6991 - Rev 8
page 9/17