Features and Benefits
- 3-Terminal Adjustable
- Output Current of 3A, 5A or 7.5A
- Operates Down to 1V Dropout
- Guaranteed Dropout Voltage at Multiple Current Levels
- Line Regulation: 0.015%
- Load Regulation: 0.1%
- 100% Thermal Limit Functional Test
- Fixed Versions Available
- Available in 3-Lead Plastic TO-220, TO-3P and DD Packages
The LT1083 series of positive adjustable regulators are designed to provide 7.5A, 5A and 3A with higher efficiency than currently available devices. All internal circuitry is designed to operate down to 1V input-to-output differential and the dropout voltage is fully specified as a function of load current. Dropout is guaranteed at a maximum of 1.5V at maximum output current, decreasing at lower load currents. On-chip trimming adjusts the reference voltage to 1%. Current limit is also trimmed, minimizing the stress on both the regulator and power source circuitry under overload conditions.
The LT1083/LT1084/LT1085 devices are pin compatible with older 3-terminal regulators. A 10μF output capacitor is required on these new devices. However, this is included in most regulator designs.
Unlike PNP regulators, where up to 10% of the output current is wasted as quiescent current, the LT1083 quiescent current flows into the load, increasing efficiency.
- High Efficiency Linear Regulators
- Post Regulators for Switching Supplies
- Constant Current Regulators
- Battery Chargers
Product Lifecycle 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.
Documentation & Resources
R006 Reliability Data3/26/201821 K
AN-140: Basic Concepts of Linear Regulator and Switching Mode Power Supplies9/1/2019
AN29 - Some Thoughts on DC-DC Converters3/8/20131M
AN32 - High Efficiency Linear Regulators9/8/2010798K
AN30 - Switching Regulator Circuit Collection10/31/2008592K
AN98 - Signal Sources, Conditioners and Power Circuitry Circuits of the Fall, 20049/4/2008864K
AN58 - 5V to 3.3V Converters for Microprocessor Systems8/20/2007302K
DN33 - Powering 3.3V Digital Systems8/12/201475K
Design Note 74: Techniques for Deriving 3.3V from 5V Supplies9/1/1993
New 3-Terminal Regulators Add Functionality7/13/2017814K
Three-Terminal Linear Regulator Evolution Continues Unabated2/19/20151M
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:
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.