The MAX1818 low-dropout linear regulator operates from a +2.5V to +5.5V supply and delivers a guaranteed 500mA load current with low 120mV dropout. The high-accuracy (1%) output voltage is preset at an internally trimmed voltage (see Selector Guide) or can be adjusted from 1.25V to 5.0V with an external resistive divider. An internal PMOS pass transistor allows the low 125A supply current to remain independent of load, making this device ideal for portable battery-operated equipment such as personal digital assistants (PDAs), cellular phones, cordless phones, base stations, and notebook computers.