Features

• Wide Input Range:
   Operation from 3.6V to 36V
   Over-Voltage Lockout Protects Circuits through  60V Transient
• 2A Maximum Output Current
• Low Ripple Burst Mode Operation
    70µA I_Q at 12V_IN to 3.3V_OUT
    Output Ripple < 15mV
• Adjustable Switching Frequency: 200kHz to 2.4MHz
• Low Shutdown Current: I_Q < 1µA
• Integrated Boost Diode
• Synchronizable Between 250kHz to 2MHz
• Power Good Flag
• Saturating Switch Design: 0.25Ω On-Resistance
• 0.790V Feedback Reference Voltage
• Output Voltage: 0.79V to 20V
• Soft-Start Capability
• Small 10-Pin Thermally Enhanced MSOP and (3mm x 3mm) DFN Packages

Typical Application

Description

The LT3480 is an adjustable frequency (200kHz to 2.4MHz) monolithic buck switching regulator that accepts input voltages up to 36V (60V maximum). A high efficiency 0.25Ω 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 LT3480 can further enhance low output current efficiency by drawing bias current from the output when V_OUT 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 V_OUT reaches 86% of the programmed output voltage. The LT3480 is available in 10-Pin MSOP and 3mm x 3mm DFN packages with exposed pads for low thermal resistance.