Patent ID: 7633252

Claim:
A stall protection circuit for use with a motor comprising: a switch for controlling powering of the motor, the switch being operable to first, second, and third states, the first state powering the motor with current flowing in a forward direction, the second state powering the motor with current flowing in a reverse direction, and the third state preventing powering of the motor; a single current sensor configured to sense current flowing in both of the forward and reverse directions; a stall detection circuit configured to compare current sensed by the single current sensor to a current threshold and to output a first signal if the current is less than the threshold and to output a second signal if the current is greater than the threshold; a first switch connected on one side of the motor and a second switch connected to an other side of the motor, each switch being controllable to an open or closed position; and a latching circuit configured to receive the first and second signals and for connecting or disconnecting the motor from the powering associated with the first or second state depending on whether the first or second signal is received, the latching circuit connecting the motor by closing both switches when the first signal is received and disconnecting the motor by opening at least one of the switches when the second signal is received.