LTC3415 7A, PolyPhase Synchronous Step-Down Regulator FEATURESDESCRIPTION n High Effi ciency: Up to 96% The LTC®3415 is a high effi ciency, monolithic synchronous n 7A Output Current at VIN = 3V buck regulator using a phase lockable constant frequency, n Adjustable Frequency: 1.5MHz Nominal current mode architecture. PolyPhase® operation allows n PolyPhase Operation (Up to 12 Phases) multiple LTC3415s to run out of phase while using mini- n Spread Spectrum Frequency Modulation mal input and output capacitance. The operating supply n Output Tracking and Margining range is from 5.5V down to 2.5V, making it suitable for n ±1% Reference Accuracy single Lithium-Ion battery as well as point of load power n 2.5V to 5.5V VIN Range supply applications. Burst Mode operation provides high n Phase Lockable from 0.75MHz to 2.25MHz effi ciency at low load currents. 100% duty cycle provides n Selectable Burst Mode® Operation low dropout operation that extends operating time in bat- n Low Dropout Operation: 100% Duty Cycle tery-operated systems. n Low Quiescent Current: 450μA The operating frequency is internally set at 1.5MHz, al- n Current Mode Operation for Excellent Line and Load lowing the use of small surface mount inductors. For Transient Response switching-noise sensitive applications, it can be externally n Shutdown Mode Draws Only 0.2μA Supply Current synchronized from 0.75MHz to 2.25MHz. The PHMODE n Available in 38-Pin (5mm × 7mm) QFN Package pin allows user control of the phase of the outgoing clock signal. The current sense comparator is factory trimmed APPLICATIONS for accurate output current sharing. Burst Mode operation is inhibited during synchronization or when the MODE pin n Point of Load Power Supply is pulled low to reduce noise and RF interference. n Portable Instruments n Distributed Power Systems , LT, LTC, LTM, Burst Mode and PolyPhase are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Battery-Powered Equipment Protected by U.S. Patents, including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131. TYPICAL APPLICATION VIN, 2.5V to 5.5V Effi ciency and Power Loss 100 10 22μF SV PV x3 IN IN 90 CLKIN SW 80 CLKOUT SW EFFICIENCY 1 POWER LOSS (W) PHMODE SW 70 V SW OUT PLLLPF 60 1.8V RUN 50 0.1 LTC3415 SW 0.2μH 47μF TRACK 40 60k x3 POWER LOSS EFFICIENCY (%) FB 30 0.01 MODE 20 2.5V PGOOD 10 3.3V ITH 5V SGND PGND 0 0.001 120k 0.01 0.1 1 10 LOAD CURRENT (A) 3415 TA01 3415 TA01B Figure 1. High Effi ciency Step-Down Converter 3415fa 1