New Content (2)
Overview
Features and Benefits
- Wide Input Operating Range: 2.7V to 36V
- Dual 1A Switches with Programmable Current Limit
- Programmable Switching Frequency: 50kHz to 1MHz
- Frequency Synchronization Up to 1MHz
- ΔVIN Compensation Using Duty Cycle Control
- Low Noise Topology
- Programmable Input Over and Undervoltage Lockout
- Cross Conduction Prevention Circuitry
- Programmable Soft-Start
- Low Shutdown Current: <1μA
- 10-Lead MSOP and DFN Packages
Product Details
The LT3999 is a monolithic, high voltage, high frequency DC/DC transformer driver providing isolated power in a small solution footprint.
The LT3999 has two 1A current limited power switches that switch out of phase. The duty cycle is programmable to adjust the output voltage. The switching frequency is programmed up to 1MHz and can be synchronized to an external clock for more accurate placement of switcher harmonics. The input operating range is programmed with the precision undervoltage and overvoltage lockouts. The supply current is reduced to less than 1μA during shutdown. A user-defined RC time constant provides an adjustable soft-start capability by limiting the inrush current at start-up.
The LT3999 is available in a 10-lead MSOP and 3mm × 3mm DFN package with exposed pad.
Applications
- Low Noise Isolated Supplies
- Medical Instrument and Safety
- Distributed Power
- Multiple Output Supplies
- Positive-to-Negative Supplies
- Noise Immunity in Data Acquisition, RS232 and RS485
Product Categories
Markets and Technologies
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.
Evaluation Kits (3)
Documentation & Resources
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R530 Reliability Data3/26/2018
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DC2049A - Demo Manual11/24/2014
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Designing Optimized Power Solutions for Precision Signal Chains (2023)10/30/2023
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Signal Chain Power: New Integrated Hardware and Software Tool for Power Design, Development and Evaluation9/6/2023
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Why Power Choices Matter in Precision Signal Chains4/12/2022
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Energy Storage Systems Boost Electric Vehicles’ Fast Charger Infrastructure3/18/2021
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Isolation for SAR ADCs5/3/2021
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Energy Storage Systems Boost Electric Vehicles’ Fast Charger Infrastructure2/1/2020 Thought Leadership
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How to Design an Isolated, High Frequency, Push-Pull DC/DC Converter4/1/2015 LT Journal
Tools & Simulations
LTspice
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Design Resources
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Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.