Dynamic protection circuit for a motor type load

摘要

An express down vehicle window lift motor drive system in which an 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.