LM1086CS-ADJ

V REG, LDO 1.5A ADJ, 1086, TO-263-3.

The LM1086CS-ADJ is a low-dropout Positive Voltage Regulator with a maximum dropout of 1.5V at 1.5A of load current. The device has the same pin-out as TIs industry standard LM317. Two resistors are required to set the output voltage of the adjustable output voltage version of the LM1086. Fixed output voltage versions integrate the adjust resistors. The LM1086 circuit includes a Zener trimmed band-gap reference, current limiting and thermal shutdown. The topology is basically that of the LM317 except for the pass transistor. Instead of a Darlington NPN with its two diode voltage drop, the LM1086 uses a single NPN. This results in a lower dropout voltage. The structure of the pass transistor is also known as a quasi LDO. The advantage of a quasi LDO over a PNP LDO is its inherently lower quiescent current. The LM1086 is specified to provide a minimum dropout voltage of 1.5V over temperature at full load.