The LM1084 is a series of low dropout voltage positive regulators with a maximum dropout of 1.5V at 5A of load current. It has the same pin-out as National Semiconductor’s industry standard LM317. The LM1084 is available in an adjustable version, which can set the output voltage with only two external resistors. It is also available in three fixed voltages: 3.3V, 5.0V and 12.0V. The fixed versions integrate the adjust resistors. The LM1084 circuit includes a zener trimmed bandgap reference, current limiting and thermal shutdown.
The LM1084 series are low‑dropout positive voltage regulators that can deliver up to 5 A with a maximum dropout of 1.5 V. The series is offered in an adjustable version and three fixed‑output versions (3.3 V, 5.0 V, 12.0 V) and is available in TO‑220 and TO‑263 packages.
Key features include current limiting, thermal shutdown, line regulation of 0.015 % (typical), load regulation of 0.1 % (typical), and an industrial temperature range of –40 °C to 125 °C. The document contains detailed electrical characteristics, typical performance graphs, ordering information, and application notes for designing stable regulator circuits.
| Maximum dropout voltage | 1.5 V at 5 A |
|---|---|
| Fixed output voltage options | 3.3 V, 5.0 V, 12.0 V |
| Line regulation (typical) | 0.015 % |
| Load regulation (typical) | 0.1 % |
| Operating temperature range | -40 °C to 125 °C |
| TO‑220 package height | 0.090‑0.110 in |
The LM1084 guarantees a minimum dropout of 1.5 V over temperature at full 5 A load.
Fixed‑output versions are offered at 3.3 V, 5.0 V, and 12.0 V.
Typical line regulation is 0.015 %.
The device operates from –40 °C to 125 °C.