1. Products
  2. Power Management
  3. Switching Regulators
  4. Flyback, Forward, and Isolated Controller
  5. LTC3803-5


Features and Benefits

  • VIN and VOUT Limited Only by External Components
  • 4.8V Undervoltage Lockout Threshold
  • Operating Junction Temperature from –55°C to 150°C
  • Adjustable Slope Compensation
  • Internal Soft-Start
  • Constant Frequency 200kHz Operation
  • ±1.5% Reference Accuracy
  • Current Mode Operation for Excellent Line and Load Transient Response
  • No Minimum Load Requirement
  • Low Quiescent Current: 240μA
  • Low Profile (1mm) SOT-23 Package

Product Details

The LTC3803-5 is a constant frequency current mode flyback controller optimized for driving N-channel MOSFETs in high input voltage applications. The LTC3803-5 operates from inputs as low as 5V. Constant frequency operation is maintained down to very light loads, resulting in less low frequency noise generation over a wide range of load currents. Slope compensation can be programmed with an external resistor.

The LTC3803-5 provides ±1.5% output voltage accuracy and consumes only 240μA of quiescent current. Ground referenced current sensing allows LTC3803-5-based converters to accept input supplies beyond the LTC3803-5’s absolute maximum VCC. For simplicity, the LTC3803-5 can be powered from a high VIN through a resistor, due to its internal shunt regulator. An internal undervoltage lockout shuts down the IC when the input voltage is too low to provide sufficient gate drive to the external MOSFET.

The LTC3803-5 is available in a low profile (1mm) 6-lead SOT-23 (ThinSOT) package.

Turn On Voltage Frequency
LTC3803 8.7V 200kHz
LTC3803-3 8.7V 300kHz
LTC3803-5 4.8V 200kHz


  • 42V and 12V Automotive Power Supplies
  • Telecom Power Supplies
  • Auxiliary/Housekeeping Power Supplies
  • Power Over Ethernet

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Tools & Simulations


LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

To launch ready-to-run LTspice demonstration circuits for this part:

Step 1: Download and install LTspice on your computer.

Step 2: Click on the link in the section below to download a demonstration circuit.

Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.


Models for the following parts are available in LTspice:


Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.

Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
LTC3803ES6-5#TRMPBF Material Declaration Reliability Data 6-Lead TSOT-23
LTC3803ES6-5#TRPBF Material Declaration Reliability Data 6-Lead TSOT-23
LTC3803HS6-5#TRMPBF Material Declaration Reliability Data 6-Lead TSOT-23
LTC3803HS6-5#TRPBF Material Declaration Reliability Data 6-Lead TSOT-23
LTC3803IS6-5#TRMPBF Material Declaration Reliability Data 6-Lead TSOT-23
LTC3803IS6-5#TRPBF Material Declaration Reliability Data 6-Lead TSOT-23
LTC3803MPS6-5#TRMPBF Material Declaration Reliability Data 6-Lead TSOT-23
LTC3803MPS6-5#TRPBF Material Declaration Reliability Data 6-Lead TSOT-23
Wafer Fabrication Data R421 Reliability Data

Sample & Buy

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Buy Now Pricing

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List Pricing

(*)The 1Ku 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 Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.


Lead Times

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