LT3045-1 - 20V, 500mA, Ultralow Noise, Ultrahigh PSRR Linear Regulator with VIOC Control


  • Ultralow RMS Noise: 0.8μVRMS (10Hz to 100kHz)
  • Ultralow Spot Noise: 2nV/√Hz at 10kHz
  • Ultrahigh PSRR: 76dB at 1MHz
  • Output Current: 500mA
  • Wide Input Voltage Range: 1.8V to 20V
  • Single Capacitor Improves Noise and PSRR
  • 100μA SET Pin Current: ±1% Initial Accuracy
  • VIOC Pin Controls Upstream Regulator to Minimize Power Dissipation
  • Single Resistor Programs Output Voltage
  • Programmable Current Limit
  • Low Dropout Voltage: 260mV
  • Output Voltage Range: 0V to 15V
  • Programmable Power Good
  • Fast Start-Up Capability
  • Precision Enable/UVLO
  • Parallelable for Lower Noise and Higher Current
  • Internal Current Limit with Foldback
  • Minimum Output Capacitor: 10μF Ceramic
  • Reverse Battery and Reverse Current Protection
  • 12-Lead MSOP and 3mm × 3mm DFN Packages

Typical Application

LT3045-1 Typical Application
LT3045-1 Typical Application


The LT®3045-1 is a high performance low dropout linear regulator featuring LTC’s ultralow noise and ultrahigh PSRR architecture for powering noise sensitive applications. Designed as a precision current reference followed by a high performance voltage buffer, the LT3045-1 can be easily paralleled to further reduce noise, increase output current and spread heat on the PCB. In addition to the LT3045 feature set, the LT3045-1 incorporates a VIOC tracking function to control an upstream switching converter to maintain a constant voltage across the LT3045-1 and hence minimize power dissipation.

The device supplies 500mA at a typical 260mV dropout voltage. Operating quiescent current is nominally 2.3mA and drops to <<1μA in shutdown. The LT3045-1’s wide output voltage range (0V to 15V) while maintaining unitygain operation provides virtually constant output noise, PSRR, bandwidth and load regulation, independent of the programmed output voltage. Additionally, the regulator features programmable current limit, fast start-up capability and programmable power good to indicate output voltage regulation.

The LT3045-1 is stable with a minimum 10μF ceramic output capacitor. Built-in protection includes reverse battery protection, reverse current protection, internal current limit with foldback and thermal limit with hysteresis. The LT3045-1 is available in thermally enhanced 12-Lead MSOP and 3mm × 3mm DFN packages.

  VIOC Function
LT3045-1 Yes
LT3045 No


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

Part Number Package Code Temp Package
LT3045EDD-1#PBF 3x3 DFN-12 DD E 05-08-1725 Yes
LT3045EDD-1#TRPBF 3x3 DFN-12 DD E 05-08-1725 Yes
LT3045EMSE-1#PBF MS-12E MSE E 05-08-1666 Yes
LT3045EMSE-1#TRPBF MS-12E MSE E 05-08-1666 Yes
LT3045IDD-1#PBF 3x3 DFN-12 DD I 05-08-1725 Yes
LT3045IDD-1#TRPBF 3x3 DFN-12 DD I 05-08-1725 Yes
LT3045IMSE-1#PBF MS-12E MSE I 05-08-1666 Yes
LT3045IMSE-1#TRPBF MS-12E MSE I 05-08-1666 Yes

LT3045-1 Package Drawing
LT3045-1 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
LT3045EDD-1#PBF 3x3 DFN-12 E $4.00 $2.80 Yes
LT3045EDD-1#TRPBF 3x3 DFN-12 E $4.06 $2.86 Yes
LT3045EMSE-1#PBF MS-12E E $4.00 $2.80 Yes
LT3045EMSE-1#TRPBF MS-12E E $4.06 $2.86 Yes
LT3045IDD-1#PBF 3x3 DFN-12 I $4.64 $3.25 Yes
LT3045IDD-1#TRPBF 3x3 DFN-12 I $4.70 $3.31 Yes
LT3045IMSE-1#PBF MS-12E I $4.64 $3.25 Yes
LT3045IMSE-1#TRPBF MS-12E I $4.70 $3.31 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
DC2593A LT3045EDD-1 Demo Board | Ultralow Noise LDO, 3.8V ≤ VIN ≤ 20V, Vout = 3.3V @ 500mA Contact Factory
DC2637A LT3045EDD-1 Demo Board | 20V, 2A (4 ICs in Parallel) Ultralow Noise, Ultrahigh PSRR LDO Regulator Contact Factory
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Click here to view our complete list of demo boards


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