Patent attributes
A power management protection circuit and method provides for a fast, real-time hardware logic control of the power control components of a motor, whereby the over-current condition is an integral of the over-current level and over-current time duration, and provides means for complete turn-off of motor voltage within a few microseconds when a specified energy level has been exceeded or an extended time for the user to take corrective actions if thermal conditions permit. Motor turn-off remains until a snubber diode current has reduced to a safe level even if the stall condition is no longer present. It allows the properties of load-dump current through the snubber diode to drive the protection control logic, and also provides for sensing the temperature of both the snubber diode and the power MOSFET switch. As temperature rises in these power devices, the trolling motor maximum voltage is reduced. Voltage control based on temperature feedback is a hardware function that operates concurrently and independently from the over-current sensing and voltage turn-off.
