Overview
Features and Benefits
- Wide Input Range: 3.6V to 36V Operating, 40V Maximum
- Up to 1.2A Output Current
- Resistor-Programmable Fixed-Frequency Operation from 200kHz to 3MHz
- Output Adjustable Down to 780mV
- Short-Circuit Robust
- Uses Tiny Capacitors and Inductors
- Soft-Start
- Low Shutdown Current: <2µA
- Low VCESAT Switch: 350mV at 1A
- Thermally Enhanced, Low Profile 3mm x 3mm DFN-8 and MSOP-8 Packages
Product Details
The LT3505 is a current mode PWM step-down DC/DC converter with an internal 1.4A power switch. The wide operating input range of 3.6V to 36V (40V maximum) makes the LT3505 ideal for regulating power from a wide variety of sources, including unregulated wall transformers, 24V industrial supplies and automotive batteries. The oscillator can be programmed for high frequency operation allowing the use of tiny, low cost external components or it can be programmed for lower frequency operation to maximize efficiency.
Cycle-by-cycle current limit provides protection against shorted outputs and soft-start eliminates input current surge during start-up. The low current (<2µA) shutdown mode provides output disconnect, enabling easy power management in battery-powered systems.
Applications
- Automotive Battery Regulation
- Industrial Control Supplies
- Wall Transformer Regulation
- Distributed Supply Regulation
- Battery-Powered Equipment
Product Categories
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 (2)
Documentation & Resources
-
R530 Reliability Data3/26/2018
-
DC1395A - Demo Manual9/24/2009
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DC1023A - Demo Manual9/24/2009
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.
LTspice Simulations
Models for the following parts are available in LTspice:
LT3505
Product Recommendations
LT3505 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 |
|---|---|---|---|---|
| LT3505EDD#PBF | Material Declaration | Reliability Data | 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP) | |
| LT3505EDD#TRPBF | Material Declaration | Reliability Data | 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP) | |
| LT3505EMS8E#PBF | Material Declaration | Reliability Data | 8-Lead MSOP w/ EP | |
| LT3505EMS8E#TRPBF | Material Declaration | Reliability Data | 8-Lead MSOP w/ EP | |
| LT3505IDD#PBF | Material Declaration | Reliability Data | 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP) | |
| LT3505IDD#TRPBF | Material Declaration | Reliability Data | 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP) | |
| LT3505IMS8E#PBF | Material Declaration | Reliability Data | 8-Lead MSOP w/ EP | |
| LT3505IMS8E#TRPBF | Material Declaration | Reliability Data | 8-Lead MSOP w/ EP | |
| Wafer Fabrication Data | R530 Reliability Data |
PCN-PDN Information
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Support & Discussions
Sample & Buy
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Lead Times
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Sampling
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Evaluation Boards
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Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
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.