The basic device in the family is the L6205. As you see in the block diagram the device implements a dual H-bridge with the gate drive and protection functions. A charge pump that uses external capacitors and diodes provides the gate drive voltage for the upper power MOS transistors. With 4 outputs, implementing the charge pump is a better choice than having the individual bootstrap capacitors like the L6202. Notice that the output of the over current detection circuit is connected to the Enable input of the IC. By putting a simple RC circuit on the enable input the part implements an over current protection that will cause the device to start chopping and limit the current to the peak set by the internal threshold. The over current detection senses the current flowing through the upper MOS transistor using a non dissipative sensing technique. By sensing this current the output can be protected against shorts across the load or shorts to ground.