Features and Benefits
- 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
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.
- 4mA to 20mA Current Loops
- Industrial Control Supplies
- Distributed Power Systems
- Portable Instruments
- Battery-Operated Devices
- Automotive Power Systems
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 (1)
Demonstration circuit DC1499A is a high efficiency step-down DC/DC converter featuring LTC3631 with internal high side and synchronous power switches that draws only 12μA quiescent current. It has a wide 4.5V to 45V input range and internal over voltage monitor capable of protecting the part through 60V surges. The jumper selectable output is up to 5V. LTC3631 can supply up to 100mA load current with a programmable peak current limit that provides a simple method for optimizing efficiency in lower current applications. With no compensation required, LTC3631 is easily configured with minimal components.
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.
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Step 2: Click on the link in the section below to download a demonstration circuit.
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Models for the following parts are available in LTspice:
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Sample & Buy
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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.