INDUCTIVE FLYBACK CLAMP CIRCUIT WITH REVERSE POLARITY PROTECTION
Original Publication Date: 1993-Jun-01
Included in the Prior Art Database: 2002-Feb-13
When driving inductive loads such as motors, dissi- When a reverse battery condition occurs there is a pating the inductor's flyback energy is a design consid- current path through the intrinsic diode of the driving era&n. A common practice is to connect a reversed device and the flyback diode. The current through this flyback diode across the inductor to provide a current path is limited only by the resistance of the diodes and recirculation path when the motor current is interrupted. the circuit wiring. This condition will ultimately cause In some applications this scheme is impractical as with irreversible damage to one or both of the electronic automotive electronics which must be protected against devices. reverse battery connections. Figure la illustrates com- monly used high and low side motor driving devices.