The L4972A is a stepdown monolithic power switching regulator delivering 2A at a voltage variable from 5.1 to 40V. Realized with BCD mixed technology, the device uses a DMOS output transistor to obtain very high efficiency and very fast switching times. Features of the L4972 include reset and power fail for microprocessors, feed forward line regulation, soft start, limiting current and thermal protection. The device is mounted in a Powerdip 16 + 2 + 2 and SO20 large plastic packages and requires few external components. Efficient operation at switching frequencies up to 200KHz allows reduction in the size and cost of external filter component.