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LT3680
36V, 3.5A, 2.4MHz Step-Down Switching Regulator with 75µA Quiescent Current
Overview
Features and Benefits
- Wide Input Voltage Range: 3.6V to 36V
- 3.5A Maximum Output Current
- Low Ripple (<15mVP-P) Burst Mode® Operation:
- IQ = 75µA at 12VIN to 3.3VOUT
- Adjustable Switching Frequency: 200kHz to 2.4MHz
- Low Shutdown Current: IQ < 0.5µA
- Integrated Boost Diode
- Synchronizable Between 250kHz to 2MHz
- Power Good Flag
- Saturating Switch Design: 95mΩ On-Resistance
- 0.790V Feedback Reference Voltage
- Output Voltage: 0.79V to 30V
- Thermal Protection
- Soft-Start Capability
- Small 10-Pin Thermally Enhanced MSOP and (3mm × 3mm) DFN Packages
Product Details
The LT3680 is an adjustable frequency (200kHz to 2.4MHz) monolithic buck switching regulator that accepts input voltages up to 36V. A high efficiency 95mΩ switch is included on the die along with a boost Schottky diode and the necessary oscillator, control, and logic circuitry. Current mode topology is used for fast transient response and good loop stability. Low ripple Burst Mode® operation maintains high efficiency at low output currents while keeping output ripple below 15mV in a typical application. In addition, the LT3680 can further enhance low output current efficiency by drawing bias current from the output when VOUT is above 3V. Shutdown reduces input supply current to less than 1µA while a resistor and capacitor on the RUN/SS pin provide a controlled output voltage ramp (soft-start). A power good flag signals when VOUT reaches 91% of the programmed output voltage. The LT3680 is available in 10-Pin MSOP and 3mm × 3mm DFN packages with exposed pads for low thermal resistance.
Applications
- Automotive Battery Regulation
- Power for Portable Products
- Distributed Supply Regulation
- Industrial Supplies
- Wall Transformer Regulation
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 (1)
Documentation
Reliability Data (1)
User Guides (1)
Spec Notice (1)
Tools & Simulations
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Reference Materials
Design Resources
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PCN-PDN Information
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Evaluation Boards
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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.