Features and Benefits
- Wide VIN Range: 1.6V (2.5V Start-Up) to 40V
- Positive or Negative Output Voltage Programming with a Single Feedback Pin
- PGOOD Output Voltage Status Report
- Internal 6A/40V Power Switch
- Programmable Soft-Start
- Programmable Operating Frequency (100kHz to 1MHz) with One External Resistor
- Synchronizable to an External Clock
- Low Shutdown Current < 1μA
- INTVCC Regulator Supplied from VIN or DRIVE
- Programmable Input Undervoltage Lockout with Hysteresis
- Thermally Enhanced QFN (5mm × 6mm) and TSSOP Packages
The LT3959 is a wide input range, current mode, DC/DC controller which is capable of regulating either positive or negative output voltages from a single feedback pin. It can be configured as a boost, SEPIC or inverting converter.
It features an internal low side N-channel MOSFET rated for 6A at 40V and driven from an internal regulated supply provided from VIN or DRIVE. The fixed frequency, current-mode architecture results in stable operation over a wide range of supply and output voltages. The operating frequency of LT3959 can be set over a 100kHz to 1MHz range with an external resistor, or can be synchronized to an external clock using the SYNC pin.
The LT3959 features soft-start and frequency foldback functions to limit inductor current during start-up and output short-circuit. A window comparator on the FBX pin reports via the PGOOD pin, providing output voltage status indication.
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 (1)
The LT3959 is a current mode DC/DC converter with an integrated 6A, 40V switch. It can operate over an input range of 1.6V to 40V, suitable for applications from singlecell lithium-ion battery portable electronics up to high voltage automotive and industrial power supplies. It also exhibits low shutdown quiescent current of <1μA, making it an ideal fit for battery-operated systems. Thanks to a novel FBX pin architecture, the LT3959 can be connected directly to a divider from either positive or negative output to ground. It also packs many popular features such as soft-start, input undervoltage lockout, adjustable frequency and synchronization. Demonstration circuit 1853A features LT3959 in a 300kHz boost converter, designed for 12V output from 2V to 10V input (VIN).
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:
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
Design tools for the following parts are available in LTpowerCAD:
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.
Sample & Buy
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 Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.