Switch Disconnect Circuit for Solar Arrays

A module for connecting (or coupling) and disconnecting (or decoupling) a photovoltaic panel (PV) to and from other PV panels in a string of PV panels. The module may include first circuitry for detecting when a voltage output by the PV panel (Vpanel) collapses, and second circuitry for disconnecting the PV panel from the panel string while preventing a transistor switching device (e.g. a power MOSFET) performing the disconnecting (decoupling) operation from entering the linear operating region. The combination of low-voltage detection in the first circuitry, and latching-switching in the second circuitry ensures that the power MOSFET is either fully turned on, coupling the PV panel to the panel string, or fully turned off, decoupling the PV panel from the panel string. The PV panel may be recoupled to the PV string through a connection-check mechanism that reengages the PV panel once Vpanel has returned to normal operating levels.