Dynamic protection for a circuit for a motor type load

摘要

An express down vehicle window lift motor drive system in which a overcurrent detection circuit (10) interprets the flow of electrical power to the lift motor when the motor current exceeds a threshold which is set dynamically as a function of motor in-rush or peak current. Motor current is measured as a small voltage drop across a current shunt. When the current level rises above the dynamically set threshold energization of the motor is halted.