LT3066 - 45V VIN, 500mA Low Noise, Linear Regulator with Programmable Current Limit and Active Output Discharge


  • Input Voltage Range: 1.8V to 45V
  • Output Current: 500mA
  • Active Output Discharge
  • Dropout Voltage: 300mV
  • Programmable Precision Current Limit: ±10%
  • Power Good Flag
  • Input Filtering for High PSRR
  • Low Noise: 25μVRMS (10Hz to 100kHz)
  • Adjustable Output (VREF = VOUT(MIN) = 600mV)
  • Output Tolerance: ±2% Over Line, Load and Temperature
  • Stable with Low ESR, Ceramic Output Capacitors (3.3μF Minimum)
  • Single Capacitor Soft-Starts Reference and Lowers Output Noise
  • Current Limit Foldback Protection
  • Shutdown Current: <3μA
  • Reverse Battery and Thermal Limit Protection
  • 12-Lead 4mm × 3mm DFN and 12-lead MSOP Packages

Typical Application

LT3066 Typical Application
LT3066 Typical Application


The LT®3066 series are micropower, low noise, low dropout voltage (LDO) linear regulators that operate over a 1.8V to 45V input voltage range. The devices supply 500mA of output current with a typical dropout voltage of 300mV. A single external capacitor provides programmable low noise reference performance and output soft-start functionality.

A single external resistor programs the LT3066’s current limit, accurate to ±10% over a wide input voltage and temperature range. A PWRGD flag indicates output regulation.

The LT3066 features an NMOS pull-down that discharges the output if SHDN or IN is driven low.

The LT3066 optimizes stability and transient response with low ESR ceramic capacitors, requiring a minimum of 3.3μF. Internal protection circuitry includes current limiting with foldback, thermal limiting, reverse battery protection, reverse current protection and reverse output protection.

The LT3066 is available in fixed output voltages of 3.3V and 5V, and as an adjustable device with an output voltage range from 0.6V to 19V. The device is offered in the thermally-enhanced 12-lead 4mm × 3mm DFN and MSOP packages.


CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

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

Part Number Package Code Temp Package
LT3066EDE-3.3#PBF 4x3 DFN-12 DE/UE E 05-08-1695 Yes
LT3066EDE-3.3#TRPBF 4x3 DFN-12 DE/UE E 05-08-1695 Yes
LT3066EDE-5#PBF 4x3 DFN-12 DE/UE E 05-08-1695 Yes
LT3066EDE-5#TRPBF 4x3 DFN-12 DE/UE E 05-08-1695 Yes
LT3066EDE#PBF 4x3 DFN-12 DE/UE E 05-08-1695 Yes
LT3066EDE#TRPBF 4x3 DFN-12 DE/UE E 05-08-1695 Yes
LT3066EMSE-3.3#PBF MS-12E MSE E 05-08-1666 Yes
LT3066EMSE-3.3#TRPBF MS-12E MSE E 05-08-1666 Yes
LT3066EMSE-5#PBF MS-12E MSE E 05-08-1666 Yes
LT3066EMSE-5#TRPBF MS-12E MSE E 05-08-1666 Yes
LT3066EMSE#PBF MS-12E MSE E 05-08-1666 Yes
LT3066EMSE#TRPBF MS-12E MSE E 05-08-1666 Yes
LT3066IDE-3.3#PBF 4x3 DFN-12 DE/UE I 05-08-1695 Yes
LT3066IDE-3.3#TRPBF 4x3 DFN-12 DE/UE I 05-08-1695 Yes
LT3066IDE-5#PBF 4x3 DFN-12 DE/UE I 05-08-1695 Yes
LT3066IDE-5#TRPBF 4x3 DFN-12 DE/UE I 05-08-1695 Yes
LT3066IDE#PBF 4x3 DFN-12 DE/UE I 05-08-1695 Yes
LT3066IDE#TRPBF 4x3 DFN-12 DE/UE I 05-08-1695 Yes
LT3066IMSE-3.3#PBF MS-12E MSE I 05-08-1666 Yes
LT3066IMSE-3.3#TRPBF MS-12E MSE I 05-08-1666 Yes
LT3066IMSE-5#PBF MS-12E MSE I 05-08-1666 Yes
LT3066IMSE-5#TRPBF MS-12E MSE I 05-08-1666 Yes
LT3066IMSE#PBF MS-12E MSE I 05-08-1666 Yes
LT3066IMSE#TRPBF MS-12E MSE I 05-08-1666 Yes

LT3066 Package Drawing
LT3066 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
LT3066EDE-3.3#PBF 4x3 DFN-12 E $2.86 $2.00 Yes
LT3066EDE-3.3#TRPBF 4x3 DFN-12 E $2.92 $2.06 Yes
LT3066EDE-5#PBF 4x3 DFN-12 E $2.86 $2.00 Yes
LT3066EDE-5#TRPBF 4x3 DFN-12 E $2.92 $2.06 Yes
LT3066EDE#PBF 4x3 DFN-12 E $2.86 $2.00 Yes
LT3066EDE#TRPBF 4x3 DFN-12 E $2.92 $2.06 Yes
LT3066EMSE-3.3#PBF MS-12E E $2.86 $2.00 Yes
LT3066EMSE-3.3#TRPBF MS-12E E $2.92 $2.06 Yes
LT3066EMSE-5#PBF MS-12E E $2.86 $2.00 Yes
LT3066EMSE-5#TRPBF MS-12E E $2.92 $2.06 Yes
LT3066EMSE#PBF MS-12E E $2.86 $2.00 Yes
LT3066EMSE#TRPBF MS-12E E $2.92 $2.06 Yes
LT3066IDE-3.3#PBF 4x3 DFN-12 I $3.14 $2.20 Yes
LT3066IDE-3.3#TRPBF 4x3 DFN-12 I $3.20 $2.26 Yes
LT3066IDE-5#PBF 4x3 DFN-12 I $3.14 $2.20 Yes
LT3066IDE-5#TRPBF 4x3 DFN-12 I $3.20 $2.26 Yes
LT3066IDE#PBF 4x3 DFN-12 I $3.14 $2.20 Yes
LT3066IDE#TRPBF 4x3 DFN-12 I $3.20 $2.26 Yes
LT3066IMSE-3.3#PBF MS-12E I $3.14 $2.20 Yes
LT3066IMSE-3.3#TRPBF MS-12E I $3.20 $2.26 Yes
LT3066IMSE-5#PBF MS-12E I $3.14 $2.20 Yes
LT3066IMSE-5#TRPBF MS-12E I $3.20 $2.26 Yes
LT3066IMSE#PBF MS-12E I $3.14 $2.20 Yes
LT3066IMSE#TRPBF MS-12E I $3.20 $2.26 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
DC2437A LT3066 Demo Board | Low Noise Linear Regulator, Active Output Discharge, 1.8V ≤ VIN ≤ 45V, Vout = 1.2/1.5/1.8/2.0/2.5/3.3/5V @ 500mA $100.00
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