LT1913 25V, 3.5A, 2.4MHz Step-Down Switching Regulator FEATURES DESCRIPTIO Wide Input Range: 3.6V to 25V The LT 1913 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 25V. 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 25V (soft-start). A power good ag signals when V reaches OUT Thermal Protection 91% of the programmed output voltage. The LT1913 is Soft-Start Capability available in 10-Pin 3mm 3mm DFN packages with ex- Small 10-Pin (3mm 3mm) DFN Packages posed 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. 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 V IN 100 5V 6.5V TO 25V 3.5A V = 12V V BD IN IN 90 RUN/SS BOOST OFF ON 0.47F 80 V = 24V IN 4.7H 15k V SW C LT1913 10F 70 RT 680pF PG 536k 60 V = 5V OUT 63.4k SYNC FB GND L = 4.7H f = 600kHz 100k 47F 50 0 0.5 1 1.5 2 2.5 3 3.5 OUTPUT CURRENT (A) 1913 TA01a 1913 G01 1913f 1 EFFICIENCY (%) U ULT1913 ABSOLUTE AXI U RATI GS (Note 1) SYNC Voltage ............................................................20V V , RUN/SS Voltage .................................................25V IN Operating Junction Temperature Range (Note 2) BOOST Pin Voltage ...................................................50V LT1913E ............................................. 40C to 125C BOOST Pin Above SW Pin .........................................25V LT1913I .............................................. 40C to 125C FB, RT, V Voltage .......................................................5V C Storage Temperature Range ................... 65C to 150C PG, BD Voltage .........................................................25V PIN CONFIGURATION TOP VIEW BD 1 10 RT BOOST 2 9 V C 11 SW 3 8 FB V 4 7 PG IN RUN/SS 5 6 SYNC DD PACKAGE 10-LEAD (3mm 3mm) PLASTIC DFN = 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 LT1913EDD PBF LT1913EDD TRPBF LDJW 10-Lead (3mm 3mm) Plastic DFN 40C to 125C LT1913IDD PBF LT1913IDD TRPBF LDJW 10-Lead (3mm 3mm) Plastic DFN 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: