POWER LOSS (mW) LTC3601 1.5A, 15V Monolithic Synchronous Step-Down Regulator FEATURES DESCRIPTION n 4V to 15V Operating Input Voltage Range The LTC 3601 is a high efficiency, monolithic synchronous n 1.5A Output Current buck regulator using a phase-lockable controlled on-time, n Up to 96% Efficiency current mode architecture capable of supplying up to 1.5A n Very Low Duty Cycle Operation: 5% at 2.25MHz of output current. The operating supply voltage range is n Adjustable Switching Frequency: 800kHz to 4MHz from 4V to 15V, making it suitable for a wide range of n External Frequency Synchronization power supply applications. n Current Mode Operation for Excellent Line and Load The operating frequency is programmable from 800kHz to Transient Response 4MHz with an external resistor enabling the use of small n User Selectable Burst Mode (No Load I = 300A) or Q surface mount inductors. For switching noise sensitive Forced Continuous Operation applications, the LTC3601 can be externally synchronized n 0.6V Reference Allows Low Output Voltages over the same frequency range. An internal phase-locked n Short-Circuit Protected loop aligns the on-time of the top power MOSFET to the n Output Voltage Tracking Capability internal or external clock. This unique constant frequency/ n Programmable Soft-Start controlled on-time architecture is ideal for high step-down n Power Good Status Output ratio applications that demand high switching frequencies n Available in Small, Thermally Enhanced 16-Pin QFN and fast transient response. (3mm 3mm) and MSOP Packages The LTC3601 offers two operational modes: Burst Mode APPLICATIONS operation and forced continuous mode to allow the user to optimize output voltage ripple, noise, and light load n Distributed Power Systems efficiency for a given application. Maximum light load n Lithium-Ion Battery-Powered Instruments efficiency is achieved with the selection of Burst Mode n Point-of-Load Power Supply operation while forced continuous mode provides minimum L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks output ripple and constant frequency operation. and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 5847554, 6580258, 6304066, 6476589, 6774611. TYPICAL APPLICATION Efficiency and Power Loss vs Load Current 100 1000 90 80 V IN V BOOST IN 4V TO 15V RUN 70 22F 0.1F 100 2.2H V OUT 60 3.3V PGOOD SW 1.5A TRACK V ON 50 180k 10pF 22F LTC3601 40 INTV FB CC 10 30 ITH 2.2F 40k RT 20 MODE/SYNC 3601 TA01a V = 5V 10 IN SGND PGND V = 12V IN 0 1 0.001 0.01 0.1 1 10 LOAD CURRENT (A) 3601 TA01b 3601fc 1 For more information www.linear.com/LTC3601 EFFICIENCY (%)LTC3601 ABSOLUTE MAXIMUM RATINGS (Note 1) SW, RUN .......................................... 0.3V to V + 0.3V V ............................................................. 0.3V to 16V IN IN SW Source Current (DC) .............................................2A V Transient Voltage ................................................18V IN Peak SW Source Current..........................................3.5A BOOST .....................................................0.3V to 18.6V Operating Junction Temperature Range BOOST-SW ................................................ 0.3V to 3.6V (Notes 2, 3) ........................................... 40C to 125C INTV ...................................................... 0.3V to 3.6V CC Storage Temperature Range .................. 65C to 125C ITH, RT.......................................0.3V to INTV + 0.3V CC Lead Temperature (Soldering, 10 sec) MODE/SYNC, FB ........................0.3V to INTV + 0.3V CC MSOP ...............................................................300C TRACK .......................................0.3V to INTV + 0.3V CC PGOOD, V ............................................... 0.3V to 16V ON PIN CONFIGURATION TOP VIEW TOP VIEW 16 15 14 13 SW 1 16 PGOOD MODE/SYNC 1 12 ITH 2 MODE/SYNC SW 15 PGND 3 14 V IN PGOOD 2 11 FB 4 PGND 13 V IN 17 17 BOOST 5 12 RUN SW 3 10 RT 6 INTV 11 TRACK CC SW 4 9 SGND V 7 10 I ON TH 8 RT 9 FB 5 6 7 8 MSE PACKAGE 16-LEAD PLASTIC MSOP T = 125C, = 38C/W JMAX JA UD PACKAGE EXPOSED PAD (PIN 17) IS SGND, MUST BE SOLDERED TO PCB 16-LEAD (3mm 3mm) PLASTIC QFN T = 125C, = 45C/W JMAX JA EXPOSED PAD (PIN 17) IS PGND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3601EUD PBF LTC3601EUD TRPBF LFJC 16-Lead (3mm 3mm) Plastic QFN 40C to 125C LTC3601IUD PBF LTC3601IUD TRPBF LFJC 16-Lead (3mm 3mm) Plastic QFN 40C to 125C LTC3601EMSE PBF LTC3601EMSE TRPBF 3601 16-Lead Plastic MSOP 40C to 125C LTC3601IMSE PBF LTC3601IMSE TRPBF 3601 16-Lead Plastic MSOP 40C to 125C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: