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LT3690
36V, 4A, 1.5MHz Synchronous Step-Down Switching Regulator with 70μA Quiescent Current
Overview
Features and Benefits
- Wide Input Range:
- Operation from 3.9V to 36V
- Overvoltage Lockout Protects Circuits Through 60V Transients
- 4A Maximum Output Current
- Integrated 30mΩ N-Channel Synchronous Switch
- Low Ripple (<15mVP-P) Burst Mode® Operation: IQ = 70µA at 12VIN to 3.3VOUT
- Programmable Input Undervoltage Lockout
- 0.8V Feedback Reference Voltage
- Output Voltage: 0.8V to 20V
- Programmable and Synchronizable Oscillator (170kHz to 1.5MHz)
- Soft-Startup and Output Voltage Tracking
- Short-Circuit Robust
- Power Good Flag
- Small Thermally Enhanced 4mm × 6mm QFN Package
Product Details
The LT®3690 is an adjustable frequency monolithic buck switching regulator that accepts input voltages up to 36V. A high efficiency 90mΩ switch is included on the device along with the boost diode and the necessary oscillator, control, and logic circuitry. The internal synchronous power switch of 30mΩ increases efficiency and eliminates the need for an external Schottky catch diode. Current mode topology is used for fast transient response and good loop stability. Shutdown reduces input supply current to less than 1µA. The low ripple Burst Mode maintains high efficiency at low output currents while keeping output ripple below 15mV in typical applications.
The LT3690 features robust operation and is easily configurable. Using a resistor divider on the UVLO pin provides a programmable undervoltage lockout. A power good flag signals when VOUT reaches 90% of the programmed output voltage. Protection circuitry senses the current in the power switches to protect the LT3690 against short-circuit conditions. Frequency foldback and thermal shutdown provide additional protection. The LT3690 is available in a 4mm × 6mm QFN package with exposed pads for low thermal resistance.
Applications
- Automotive Systems
- Industrial Supplies
- Distributed Supply 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)
Tools & Simulations
LTspice
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Reference Materials
Product Selection Guide (1)
Videos (1)
Switching Regulator Power Loss
Design Resources
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Support & Discussions
LT3690 Discussions
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
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