LT3085 - Adjustable 500mA Single Resistor Low Dropout Regulator


  • Outputs May be Paralleled for Higher Current and Heat Spreading
  • Output Current: 500mA
  • Single Resistor Programs Output Voltage
  • 1% Initial Accuracy of SET Pin Current
  • Output Adjustable to 0V
  • Current Limit Constant with Temperature
  • Low Output Noise: 40μVRMS (10Hz to 100kHz)
  • Wide Input Voltage Range: 1.2V to 36V
  • Low Dropout Voltage: 275mV
  • < 1mV Load Regulation
  • < 0.001%/ V Line Regulation
  • Minimum Load Current: 0.5mA
  • Stable with Minimum 2.2μF Ceramic Capacitor
  • Current Limit with Foldback and Overtemperature Protected
  • 8-Lead MSOP, and 6-Lead 2mm × 3mm DFN Packages

Typical Application

LT3085 Typical Application
LT3085 Typical Application


The LT3085 is a 500mA low dropout linear regulator that can be paralleled to increase output current or spread heat on surface mounted boards. Designed as a precision current source and voltage follower, this new regulator finds use in many applications requiring high current, adjustability to zero, and no heat sink. The device also brings out the collector of the pass transistor to allow low dropout operation—down to 275mV—when used with a second supply.

A key feature of the LT3085 is the capability to supply a wide output voltage range. By using a reference current through a single resistor, the output voltage is programmed to any level between zero and 36V. The LT3085 is stable with 2.2μF of capacitance on the output, and the IC uses small ceramic capacitors that do not require additional ESR as is common with other regulators.

Internal protection circuitry includes current limiting and thermal limiting. The LT3085 is offered in the 8-lead MSOP and a low profile (0.75mm) 6-lead 2mm × 3mmDFN package (both with an Exposed Pad for better thermal characteristics).


For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
LT3085EDCB#PBF 2x3 DFN-6 DCB E 05-08-1715 RoHS
LT3085EDCB#TRMPBF 2x3 DFN-6 DCB E 05-08-1715 RoHS
LT3085EDCB#TRPBF 2x3 DFN-6 DCB E 05-08-1715 RoHS
LT3085EMS8E#PBF MS-8 MS8 E 05-08-1660 RoHS
LT3085EMS8E#TRPBF MS-8 MS8 E 05-08-1660 RoHS
LT3085IDCB#PBF 2x3 DFN-6 DCB I 05-08-1715 RoHS
LT3085IDCB#TRMPBF 2x3 DFN-6 DCB I 05-08-1715 RoHS
LT3085IDCB#TRPBF 2x3 DFN-6 DCB I 05-08-1715 RoHS
LT3085IMS8E#PBF MS-8 MS8 I 05-08-1660 RoHS
LT3085IMS8E#TRPBF MS-8 MS8 I 05-08-1660 RoHS
LT3085MPMS8E MS-8 MS8 MP 05-08-1660 RoHS
LT3085MPMS8E#PBF MS-8 MS8 MP 05-08-1660 RoHS
LT3085MPMS8E#TR MS-8 MS8 MP 05-08-1660 RoHS
LT3085MPMS8E#TRPBF MS-8 MS8 MP 05-08-1660 RoHS

LT3085 Package Drawing
LT3085 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
LT3085EDCB#PBF 2x3 DFN-6 E $2.47 Yes
LT3085EDCB#TRMPBF 2x3 DFN-6 E $2.47 $1.78 Yes
LT3085EDCB#TRPBF 2x3 DFN-6 E $2.47 $1.73 Yes
LT3085EMS8E#PBF MS-8 E $2.62 $1.83 Yes
LT3085EMS8E#TRPBF MS-8 E $1.89 Yes
LT3085IDCB#PBF 2x3 DFN-6 I $2.71 Yes
LT3085IDCB#TRMPBF 2x3 DFN-6 I $2.71 $1.95 Yes
LT3085IDCB#TRPBF 2x3 DFN-6 I $2.71 $1.90 Yes
LT3085IMS8E#PBF MS-8 I $2.86 $2.00 Yes
LT3085IMS8E#TRPBF MS-8 I $2.06 Yes
LT3085MPMS8E MS-8 MP $7.06 $4.94 No
LT3085MPMS8E#PBF MS-8 MP $7.06 $4.94 Yes
LT3085MPMS8E#TR MS-8 MP $5.00 No
LT3085MPMS8E#TRPBF MS-8 MP $5.00 Yes
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1401A LT3085EDCB Demo Board | Single Resistor, Low Dropout Regulator, 1.7V ≤ VIN ≤ 25V, Vout = 1.2V/1.8V/2.5V/3.3V/5V/Adj @ 500mA $75.00
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  • High Current All Surface Mount Supply
  • High Efficiency Linear Regulator
  • Post Regulator for Switching Supplies
  • Low Parts Count Variable Voltage Supply
  • Low Output Voltage Power Supplies

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