Overview
Features and Benefits
- 2.5V to 36V Input Voltage Range
- Programmable Switching Frequency from 500kHz to 2.1MHz
- Synchronizable Up to 2.75MHz
- VOUT(MIN): 0.8V
- Independent Soft-Start for Each Converter
- Separate VIN Supplies for Each Converter
- Duty Cycle Range: 0% to 90% at 1MHz
- Available in 24-Lead (4mm × 4mm) QFN and 20-Lead TSSOP Packages
Product Details
The LT3570 is a buck and boost converter with internal power switches and LDO controller. Each converter is designed with a 1.5A current limit and an input range from 2.5V to 36V, making the LT3570 ideal for a wide variety of applications. Switching frequencies up to 2.1MHz are programmed with an external timing resistor and the oscillator can be synchronized to an external clock up to 2.75MHz.
The LT3570 features a programmable soft-start function that limits the feedback voltage during start-up helping prevent overshoot and limiting inrush current. The LDO controller is capable of delivering up to 10mA of base current to an external NPN transistor.
Applications
- Cable and Satellite Set-Top Boxes
- Automotive Systems
- Telecom Systems
- “Dying Gasp” Systems
- TFT LCD Displays
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)
Documentation & Resources
-
R530 Reliability Data3/26/2018
-
DC1106A - Demo Manual9/24/2009
-
Buck, Boost and LDO Regulators Combined in a 4mm × 4mm QFN6/1/2008 LT Journal
Tools & Simulations
LTspice
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:
Product Recommendations
LT3570 Companion Parts
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 |
---|---|---|---|---|
LT3570EFE#PBF | Material Declaration | Reliability Data | 20-Lead TSSOP w/ EP | |
LT3570EFE#TRPBF | Material Declaration | Reliability Data | 20-Lead TSSOP w/ EP | |
LT3570EUF#PBF | Material Declaration | Reliability Data | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | |
LT3570EUF#TRPBF | Material Declaration | Reliability Data | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | |
LT3570IFE#PBF | Material Declaration | Reliability Data | 20-Lead TSSOP w/ EP | |
LT3570IFE#TRPBF | Material Declaration | Reliability Data | 20-Lead TSSOP w/ EP | |
LT3570IUF#PBF | Material Declaration | Reliability Data | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | |
LT3570IUF#TRPBF | Material Declaration | Reliability Data | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | |
Wafer Fabrication Data | R530 Reliability Data |
PCN-PDN Information
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Support & Discussions
Sample & Buy
Ordering FAQs
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Buy Now Pricing
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List Pricing
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Lead Times
Please see the latest communication from our CCO regarding lead times.
Sampling
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