POWER LOSS (W) LTC3622/ LTC3622-2/LTC3622-23/5 17V, Dual 1A Synchronous Step-Down Regulator with Ultralow Quiescent Current FEATURES DESCRIPTION n Dual Step-Down Outputs: 1A Per Channel The LTC 3622 is a dual 1A output, high efficiency synchro- n Wide V Range: 2.7V to 17V nous monolithic step-down regulator capable of operating IN n Wide V Range: 0.6V to V from input supplies up to 17V. The switching frequency is OUT IN n Up to 95% Efficiency fixed to 1MHz or 2.25MHz with a 50% synchronization n No-Load I = 5A with Both Channels Enabled range to an external clock. The regulator features ultralow Q I < 4A with Only One Channel Enabled quiescent current and high efficiency over a wide output Q n High Efficiency, Low Dropout Operation voltage range. (100% Duty Cycle) The step-down regulators operate from an input voltage n Constant Frequency (1MHz/2.25MHz) with External range of 2.7V to 17V and provide an adjustable output Frequency Synchronization from 0.6V to V while delivering up to 1A of output cur- IN n 1% Output Voltage Accuracy rent. A user-selectable mode input is provided to allow n Current Mode Operation for Excellent Line and Load the user to trade off ripple noise for light load efficiency. Transient Response Burst Mode operation provides the highest efficiency at n Phase Shift Programmable with External Clock light loads, while pulse-skipping mode provides the lowest n Selectable Current Limit ripple noise. The switching regulators can be synchronized n Internal Compensation and Soft-Start to an external clock. Furthermore, fixed V options are OUT n Compact 14-Pin DFN (3mm 4mm) and 16-Lead available to eliminate the external feedback resistors. MSOP Packages List of LTC3622 Options PART NAME FREQUENCY V OUT APPLICATIONS LTC3622 1.00MHz Adjustable n Battery Powered Systems LTC3622-2 2.25MHz Adjustable n Point-of-Load Supplies LTC3622-23/5 2.25MHZ 5V/3.3V n Portable Handheld Scanners All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 6580258, 6498466, 6611131, 5705919. TYPICAL APPLICATION Efficiency vs Load Current 2.5V/5V V Application, f = 1MHz OUT SW 100 0.6 90 V IN V INTV IN1 CC 5.5V TO 17V 0.5 80 V IN2 MODE/SYNC C C1 IN 70 RUN1 0.4 10F 1F RUN2 PHASE 60 I LIM 50 0.3 LTC3622 40 V 4.7H 6.8H V 0.2 V = 2.5V OUT1 OUT2 OUT1 30 2.5V SW1 SW2 5V V = 5V OUT2 1A 1A 20 V = 12V IN 0.1 22pF 619k 619k 22pF f = 1MHz SW C C 10 OUT1 OUT2 FB1 FB2 Burst Mode OPERATION 22F 22F GND 0 0 196k 84.5k 0.0001 0.001 0.01 0.1 1 LOAD CURRENT (A) 3622 TA01b 3622 TA01 Rev D 1 Document Feedback For more information www.analog.com EFFICIENCY (%)LTC3622/ LTC3622-2/LTC3622-23/5 TABLE OF CONTENTS Features ............................................................................................................................ 1 Applications ....................................................................................................................... 1 Typical Application ............................................................................................................... 1 Description......................................................................................................................... 1 Absolute Maximum Ratings ..................................................................................................... 3 Pin Configuration ................................................................................................................. 3 Order Information ................................................................................................................. 3 Electrical Characteristics ........................................................................................................ 4 Typical Performance Characteristics .......................................................................................... 6 Pin Functions ...................................................................................................................... 9 Block Diagram ....................................................................................................................10 Operation..........................................................................................................................11 Applications Information .......................................................................................................13 Typical Applications .............................................................................................................20 Package Description ............................................................................................................21 Revision History .................................................................................................................23 Typical Application ..............................................................................................................24 Related Parts .....................................................................................................................24 Rev D 2 For more information www.analog.com