LT3680EDD#PBF Analog Devices

LT3680 36V, 3.5A, 2.4MHz Step-Down Switching Regulator with 75A Quiescent Current FEATURES DESCRIPTION Wide Input Voltage Range: 3.6V to 36V The LT 3680 is an adjustable frequency (200kHz to 3.5A Maximum Output Current 2.4MHz) monolithic buck switching regulator that accepts Low Ripple (<15mV ) Burst Mode Operation: input voltages up to 36V. A high efficiency 95m switch P-P I = 75A at 12V to 3.3V is included on the die along with a boost Schottky diode Q IN OUT Adjustable Switching Frequency: 200kHz to 2.4MHz and the necessary oscillator, control, and logic circuitry. Low Shutdown Current: I < 0.5A Current mode topology is used for fast transient response Q Integrated Boost Diode and good loop stability. Low ripple Burst Mode operation Synchronizable Between 250kHz to 2MHz maintains high efficiency at low output currents while Power Good Flag keeping output ripple below 15mV in a typical application. Saturating Switch Design: 95m On-Resistance In addition, the LT3680 can further enhance low output 0.790V Feedback Reference Voltage current efficiency by drawing bias current from the output Output Voltage: 0.79V to 30V when V is above 3V. Shutdown reduces input supply OUT Thermal Protection current to less than 1A while a resistor and capacitor on Soft-Start Capability the RUN/SS pin provide a controlled output voltage ramp Small 10-Pin Thermally Enhanced MSOP and (soft-start). A power good flag signals when V reaches OUT (3mm 3mm) DFN Packages 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 All registered trademarks and trademarks are the property of their respective owners. Automotive Battery Regulation Power for Portable Products Distributed Supply Regulation Industrial Supplies Wall Transformer Regulation TYPICAL APPLICATION 5V Step-Down Converter Efficiency V OUT 100 V IN 5V 6.3V TO 36V 3.5A V = 12V IN V BD IN 90 RUN/SS BOOST OFF ON V = 34V IN 80 V = 24V IN 0.47F 4.7H 15k V SW C LT3680 10F 70 RT 680pF PG 60 V = 5V OUT 536k 63.4k SYNC L = 4.7H FB GND f = 600kHz 50 100k 47F 0 0.5 1 1.5 2 2.5 3 3.5 OUTPUT CURRENT (A) 3680 TA01a 3680 G01 Rev C 1 Document Feedback For more information www.analog.com EFFICIENCY (%)LT3680 ABSOLUTE MAXIMUM RATINGS (Note 1) Operating Junction Temperature Range (Note 2) V , RUN/SS Voltage .................................................36V IN LT3680E ............................................ 40C to 125C BOOST Pin Voltage ...................................................56V LT3680I ............................................. 40C to 125C BOOST Pin Above SW Pin .........................................30V LT3680H ............................................ 40C to 150C FB, RT, V Voltage .......................................................5V C Storage Temperature Range .................. 65C to 150C PG, BD, SYNC Voltage ..............................................30V Lead Temperature (Soldering, 10 sec) (MSE Only) .......................................................300C PIN CONFIGURATION TOP VIEW TOP VIEW BD 10 RT 1 BD 1 10 RT BOOST 2 9 V C BOOST 2 9 V C 11 11 SW 3 8 FB SW 3 8 FB V 4 7 PG IN V 4 7 PG IN RUN/SS 5 6 SYNC RUN/SS 5 6 SYNC MSE PACKAGE 10-LEAD PLASTIC MSOP DD PACKAGE = 45C/W, = 10C/W JA JC 10-LEAD (3mm 3mm) PLASTIC DFN EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB = 45C/W, = 10C/W JA JC EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION