(ACTIVE) 3A Fixed / Adjustable Output Linear Regulator


Functional diagram

Function Block Diagram

Typical Performance

Typical Application


The LM1085 is a regulator with a maximum dropout of 1.5 V at 3 A of load current. It has the same pin-out as TI’s industry standard LM317.

Two resistors are required to set the output voltage of the adjustable output voltage version of the LM1085. Fixed output voltage versions integrate the adjust resistors.

The LM1085 circuit includes a zener trimmed bandgap reference, current limiting and thermal shutdown.

Refer to the LM1084 for the 5A version, and the LM1086 for the 1.5A version.


  • Available in 3.3-V, 5.0-V, 12-V and
    Adjustable Versions
  • Current Limiting and Thermal Protection
  • Output Current 3 A
  • Line Regulation 0.015% (typical)
  • Load Regulation 0.1% (typical)


Iout (Max) (A) 3   
Output Options Adjustable Output^Fixed Output   
Vin (Min) (V) 2.6   
Vin (Max) (V) 29   
Fixed Output Options (V) 3.3^5^12   
Vout (Min) (V) 1.25   
Vout (Max) (V) 27.5   
Iq (Typ) (mA) 5   
Vdo (Typ) (mV) 1300   
Accuracy (%) 4   
Noise (uVrms) 38   
PSRR @ 100KHz (dB) 30   
Output Capacitor Type Non-Ceramic   
Rating Catalog   
Operating Temperature Range (C) -40 to 125   
Pin/Package 3DDPAK/TO-263^3TO-220   

Companion Products

Technical Documents

Datasheet (1)

Application notes (7)

Selection guides (4)

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