LTC3631 - High Efficiency, High Voltage 100mA Synchronous Step-Down Converter
Features
- Wide Input Voltage Range: Operation from 4.5V to 45V
- Overvoltage Lockout Provides Protection Up to 60V
- Internal High Side and Low Side Power Switches
- No Compensation Required
- 100mA Output Current
- Low Dropout Operation: 100% Duty Cycle
- Low Quiescent Current: 12μA
- 0.8V ±1% Feedback Voltage Reference
- Adjustable Peak Current Limit
- Internal and External Soft-Start
- Precise RUN Pin Threshold with Adjustable Hysteresis
- 3.3V, 5V and Adjustable Output Versions
- Only Three External Components Required for Fixed Output Versions
- Low Profile (0.75mm) 3mm × 3mm DFN and Thermally-Enhanced MS8E Packages
Typical Application
Description
The LTC3631 is a high voltage, high efficiency step-down DC/DC converter with internal high side and synchronous power switches that draws only 12μA typical DC supply current at no load while maintaining output voltage regulation.
The LTC3631 can supply up to 100mA load current and features a programmable peak current limit that provides a simple method for optimizing efficiency in lower current applications. The LTC3631’s combination of Burst Mode® operation, integrated power switches, low quiescent current, and programmable peak current limit provides high efficiency over a broad range of load currents.
With its wide 4.5V to 45V input range and internal overvoltage monitor capable of protecting the part from 60V surges, the LTC3631 is a robust converter suited for regulating a wide variety of power sources. Additionally, the LTC3631 includes a precise run threshold and a soft‑start feature to guarantee that power system start-up is well-controlled in any environment.
The LTC3631 is available in the thermally enhanced 3mm × 3mm DFN and MS8E packages.
Packaging
For complete and up to date package information and drawings, please refer to our packaging page
DFN-8, MS-8
Order Info
- Part numbers ending in PBF are lead free. Please contact LTC marketing for information on lead based finish parts.
- Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
- Please refer to our general ordering information or the product datasheet for more details
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) | Price (1k)* | RoHS Data |
|---|---|---|---|---|---|---|
| LTC3631EDD#PBF | DFN | 8 | E | $4.22 | $2.95 | View |
| LTC3631EDD#TRPBF | DFN | 8 | E | $3.01 | View | |
| LTC3631EDD-3.3#PBF | DFN | 8 | E | $4.22 | $2.95 | View |
| LTC3631EDD-3.3#TRPBF | DFN | 8 | E | $3.01 | View | |
| LTC3631EDD-5#PBF | DFN | 8 | E | $4.22 | $2.95 | View |
| LTC3631EDD-5#TRPBF | DFN | 8 | E | $3.01 | View | |
| LTC3631EMS8E#PBF | MSOP | 8 | E | $4.22 | $2.95 | View |
| LTC3631EMS8E#TRPBF | MSOP | 8 | E | $3.01 | View | |
| LTC3631EMS8E-3.3#PBF | MSOP | 8 | E | $4.22 | $2.95 | View |
| LTC3631EMS8E-3.3#TRPBF | MSOP | 8 | E | $3.01 | View | |
| LTC3631EMS8E-5#PBF | MSOP | 8 | E | $4.22 | $2.95 | View |
| LTC3631EMS8E-5#TRPBF | MSOP | 8 | E | $3.01 | View | |
| LTC3631IDD#PBF | DFN | 8 | I | $4.84 | $3.39 | View |
| LTC3631IDD#TRPBF | DFN | 8 | I | $3.45 | View | |
| LTC3631IDD-3.3#PBF | DFN | 8 | I | $4.84 | $3.39 | View |
| LTC3631IDD-3.3#TRPBF | DFN | 8 | I | $3.45 | View | |
| LTC3631IDD-5#PBF | DFN | 8 | I | $4.84 | $3.39 | View |
| LTC3631IDD-5#TRPBF | DFN | 8 | I | $3.45 | View | |
| LTC3631IMS8E#PBF | MSOP | 8 | I | $4.84 | $3.39 | View |
| LTC3631IMS8E#TRPBF | MSOP | 8 | I | $3.45 | View | |
| LTC3631IMS8E-3.3#PBF | MSOP | 8 | I | $4.84 | $3.39 | View |
| LTC3631IMS8E-3.3#TRPBF | MSOP | 8 | I | $3.45 | View | |
| LTC3631IMS8E-5#PBF | MSOP | 8 | I | $4.84 | $3.39 | View |
| LTC3631IMS8E-5#TRPBF | MSOP | 8 | I | $3.45 | View | |
| Buy Now • Request Samples | ||||||
Demo Boards
Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC1499A | LTC3631EDD Demo Board | High Efficiency, High Voltage 100mA Synchronous Step-Down Converter | $100.00 | |
| Buy Now | |||
Applications
- 4mA to 20mA Current Loops
- Industrial Control Supplies
- Distributed Power Systems
- Portable Instruments
- Battery-Operated Devices
- Automotive Power Systems
People Who Viewed This Product Also Viewed
- LTC3642 - High Efficiency, High Voltage 50mA Synchronous Step-Down Converter
- LT3990 - 62V, 350mA Step-Down Regulator with 2.5μA Quiescent Current and Integrated Diodes
- LT3470 - Micropower Buck Regulator with Integrated Boost and Catch Diodes
- LTC3630 - High Efficiency, 65V 500mA Synchronous Step-Down Converter
- LTC3632 - High Efficiency, High Voltage 20mA Synchronous Step-Down Converter
- LT8610 - 42V, 2.5A Synchronous Step-Down Regulator with 2.5μA Quiescent Current
- LT3970 Series - 40V, 350mA Step-Down Regulator with 2.5μA Quiescent Current and Integrated Diodes
- LT4363 - High Voltage Surge Stopper with Current Limit
- LT1934 - Micropower Step-Down Switching Regulators in ThinSOT
- LTC3388 - 20V High Efficiency Nanopower Step-Down Regulator
Product Notifications
Please login to your MyLinear account for notifications of datasheet updates, new document releases and LTspice model announcements for your favorite products. If you do not have a MyLinear account you may Sign Up Now.
Forgot your password? Click here.
Need help? Email mylinear@linear.com with questions and comments.
Simulate
LTspice IV is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. To download LTspice IV and other FREE simulation tools, please visit our Design Simulation page.
To launch a ready to run LTspice demonstration circuit for this part:
- Step 1: If you have not installed LTspice on this computer, download and install LTspice IV
- Step 2: Once LTspice is installed, click on the link(s) below to launch the simulation
- Step 3: If LTspice IV does not automatically open after clicking the link above, 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
To explore other ready to run LTspice demonstration circuits, please visit our Demo Circuits Collection.
Related models available in LTspice IV
LTC3631-3.3
LTC3631-5
LTC3631
Technical Support
- For immediate technical assistance, contact your local sales office or distributor or call 1-800-4-LINEAR (US customers only) or 408-432-1900.
- For less urgent requests, please complete our Technical Support Request Form. Please allow 2-3 business days for reply.
