LT3684 - 36V, 2A, 2.8MHz Step-Down Switching Regulator

The LT3684 is an adjustable frequency (300kHz to 2.8MHz) monolithic buck switching regulator that accepts input voltages up to 34V (36V maximum). A high efficiency 0.18Ω 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. The LT3684’s high operating frequency allows the use of small, low cost inductors and ceramic capacitors resulting in low output ripple while keeping total solution size to a minimum. The low current shutdown mode 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 90% of the programmed output voltage. The LT3684 is available in 10-Pin MSOP and 3mm × 3mm DFN packages with Exposed Pads for low thermal resistance.

Features
  • Wide Input Range: 3.6V to 34V Operating, 36V Maximum
  • 2A Maximum Output Current
  • Adjustable Switching Frequency: 300kHz to 2.8MHz
  • Low Shutdown Current: IQ < 1µA
  • Integrated Boost Diode
  • Power Good Flag
  • Saturating Switch Design: 0.18Ω On-Resistance
  • 1.265V Feedback Reference Voltage
  • Output Voltage: 1.265V to 20V
  • Soft-Start Capability
  • Small 10-Pin Thermally Enhanced MSOP and (3mm × 3mm) DFN Packages
Typical Application

Applications
  • Automotive Battery Regulation
  • Power for Portable Products
  • Distributed Supply Regulation
  • Industrial Supplies
  • Wall Transformer Regulation
Packaging

Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
LT3684EDD#PBF3x3 DFN-10E$4.21$2.95
LT3684EDD#TRPBF3x3 DFN-10E$3.01
LT3684EMSE#PBFMS-10EE$4.36$3.05
LT3684EMSE#TRPBFMS-10EE$3.11
LT3684IDD#PBF3x3 DFN-10I$5.06$3.54
LT3684IDD#TRPBF3x3 DFN-10I$3.60
LT3684IMSE#PBFMS-10EI$5.20$3.64
LT3684IMSE#TRPBFMS-10EI$3.70
Demo Boards
Part NumberDescriptionPrice
DC1188ALT3684EMSE Demo Board | 4.5V ≤ VIN ≤ 34V, Vout = 3.3V @ 2A$150.00
Datasheet
Reliability Data
Press Release
LTspice
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