LT1912 Datasheet | Linear Technology

LT1912 36V, 2A, 500k Hz Step-Down Switching Regulator Features Wide Input Range: Operation From 3.6V to 36V - 2A Maximum Output Current - Adjustable Switching Frequency: 200k Hz to 500k Hz - Low Shutdown Current: I < 1μA Q .. - Integrated Boost Diode - Synchronizable Between 250k Hz to 500k Hz - 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 × 3mm) DFN Packages - DESCRIPTION The LT®1912 is an adjustable frequency (200k Hz to 500k Hz) monolithic step-down switching regulator that accepts input voltages up to 36V. 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. The LT1912 allows the use of 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). The LT1912 is available in 10-Pin MSOP and 3mm × 3mm DFN packages with exposed pads for low thermal resistance. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. APPLICATIONS - - - - - Automotive Battery Regulation Set Top Box Distributed Supply Regulation Industrial Supplies Wall Transformer Regulation TYPICAL APPLICATION 3.3V Step-Down Converter VIN 4.5V TO 36V VIN OFF ON 20k 4.7μF 470p F 68.1k VC RT 316k GND FB 100k 47μF 50 0 1912 TA01 Efficiency VOUT 3.3V 2A 100 VOUT = 5V 90 EFFICIENCY (%) VOUT = 3.3V BD BOOST 0.47μF LT1912 SW 6.8μH RUN/SS 60 VIN = 12V L = 6.8μF F = 500k Hz 0.5 1.0 1.5 LOAD CURRENT (A) 2 1912...