Patent ID: 8649141

Claim:
A by-pass circuit for a photovoltaic panel comprising an array of cells having an anode and a cathode, the by-pass circuit comprising: a first power MOS transistor including an intrinsic diode and comprising a first conduction terminal to be coupled to the cathode, a second conduction terminal to be coupled to the anode, and a control terminal; a tank capacitor to be coupled to the anode; a second MOS transistor comprising a first conduction terminal, a second conduction terminal, a control terminal, and having a turn-on threshold smaller than that of said intrinsic diode of said first power MOS transistor, the first conduction terminal of said second MOS transistor to be coupled to the cathode and the control terminal to be coupled to the anode, so that said first MOS transistor turns on when the array of cells are sub-illuminated or failed; an oscillator and a charge pump coupled to the second conduction terminal of said second MOS transistor to charge said tank capacitor; and a control circuit coupled to the control terminal of said first power MOS transistor and configured to switch said first power MOS transistor on based upon a voltage of said tank capacitor and a sign of the voltage between the cathode and the anode, said control circuit comprising a comparator circuit configured to compare a voltage of said tank capacitor with a threshold voltage, said comparator circuit comprising a voltage divider coupled across said tank capacitor and having an intermediate node, and a comparator having a first input coupled to the intermediate node and a second input coupled to the threshold voltage.