LT3693 36V, 3.5A, 2.4MHz Step-Down Switching Regulator FEATURES DESCRIPTIO Wide Input Range: 3.6V to 36V The LT 3693 is an adjustable frequency (200kHz to 3.5A Maximum Output Current 2.4MHz) monolithic buck switching regulator that accepts Adjustable Switching Frequency: 200kHz to 2.4MHz input voltages up to 36V. A high ef ciency 95m switch Low Shutdown Current: I < 1A is included on the die along with a boost Schottky diode Q Integrated Boost Diode and the necessary oscillator, control, and logic circuitry. Synchronizable Between 250kHz to 2MHz Current mode topology is used for fast transient response Power Good Flag and good loop stability. Shutdown reduces input supply Saturating Switch Design: 95m On-Resistance current to less than 1A while a resistor and capacitor on 0.790V Feedback Reference Voltage the RUN/SS pin provide a controlled output voltage ramp Output Voltage: 0.79V to 30V (soft-start). A power good ag signals when V reaches OUT Thermal Protection 91% of the programmed output voltage. The LT3693 is Soft-Start Capability available in 10-Pin MSOP and 3mm 3mm DFN packages Small 10-Pin Thermally Enhanced MSOP and with exposed pads for low thermal resistance. (3mm 3mm) DFN Packages , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. U APPLICATIO S Automotive Battery Regulation Power for Portable Products Distributed Supply Regulation Industrial Supplies Wall Transformer Regulation TYPICAL APPLICATIO 5V Step-Down Converter Ef ciency 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 0.47 F 4.7 H 15k V SW C LT3693 10 F 70 RT 680pF PG 60 V = 5V 536k OUT 63.4k SYNC L = 4.7H FB GND f = 600kHz 50 100k 47 F 0 0.5 1 1.5 2 2.5 3 3.5 OUTPUT CURRENT (A) 3693 TA01a 3693 G01 3693f 1 EFFICIENCY (%) U ULT3693 ABSOLUTE AXI U RATI GS (Note 1) Operating Junction Temperature Range (Note 2) V , RUN/SS Voltage .................................................36V IN LT3693E ............................................. 40C to 125C BOOST Pin Voltage ...................................................56V LT3693I.............................................. 40C to 125C BOOST Pin Above SW Pin .........................................30V Storage Temperature Range ................... 65C to 150C FB, RT, V Voltage .......................................................5V C Lead Temperature (Soldering, 10 sec) PG, BD Voltage .........................................................30V (MSE Only) ....................................................... 300C SYNC Voltage ............................................................20V PIN CONFIGURATION TOP VIEW TOP VIEW BD 1 10 RT BD 1 10 RT BOOST 2 9 V C BOOST 2 9 V C 11 SW 3 11 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 LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3693EDD PBF LT3693EDD TRPBF LDGB 10-Lead (3mm 3mm) Plastic DFN 40C to 125C LT3693IDD PBF LT3693IDD TRPBF LDGB 10-Lead (3mm 3mm) Plastic DFN 40C to 125C LT3693EMSE PBF LT3693EMSE TRPBF LTDFZ 10-Lead Plastic MSOP 40C to 125C LT3693IMSE PBF LT3693IMSE TRPBF LTDFZ 10-Lead Plastic MSOP 40C to 125C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based nish parts. For more information on lead free part marking, go to: