The L4955 is a family of monolithic ultra very low drop linear regulators designed to supply the most recent microprocessors.
The dropout voltage is only 0.75V (Typ.) at 5A, directly dependent on the output current conditions. Realized in BCDII technology, it has on board a charge pump to properly drive an N-channel power mos Transistor with 150mΩ of RDSON.
It operates from a 4.5V minimum supply, with a very low quiescent current irrespective of the load; a