POWER LOSS (W) LTC3417A Dual Synchronous 1.5A/1A 4MHz Step-Down DC/DC Regulator Fea T Descrip T n High Efficiency: Up to 95% The LTC 3417A is a dual constant frequency, synchronous n 1.5A/1A Guaranteed Minimum Output Current step-down DC/DC converter. Intended for medium power n Synchronizable to External Clock applications, it operates from a 2.25V to 5.5V input volt- n No Schottky Diodes Required age range and has a constant programmable switching n Programmable Frequency Operation: 1.5MHz or frequency, allowing the use of tiny, low cost capacitors Adjustable From 0.6MHz to 4MHz and inductors 2mm or less in height. Each output voltage n Low R Internal Switches is adjustable from 0.8V to 5V. Internal, synchronous, low DS(ON) n Short-Circuit Protected R power switches provide high efficiency without DS(ON) n V : 2.25V to 5.5V the need for external Schottky diodes. IN n Current Mode Operation for Excellent Line and Load A user selectable mode input allows the user to trade Transient Response off ripple voltage for light load efficiency. Burst Mode n 125A Quiescent Current in Sleep Mode operation provides high efficiency at light loads, while n Ultralow Shutdown Current: I < 1A Q Pulse Skip mode provides low ripple noise at light loads. n Low Dropout Operation: 100% Duty Cycle A phase mode pin allows the second channel to operate n Power Good Output in-phase or 180 out-of-phase with respect to channel 1. n Phase Pin Selects 2nd Channel Phase Relationship Out-of-phase operation produces lower RMS current on V IN with Respect to 1st Channel and thus a lower RMS derating on the input capacitor. n Internal Soft-Start with Individual Run Pin Control n To further maximize battery life, the P-channel MOSFETs Available in Small Thermally Enhanced are turned on continuously in dropout (100% duty cycle) (5mm 3mm) DFN and 20-Lead TSSOP Packages and both channels draw a total quiescent current of only a T 125A. In shutdown, the device draws <1A. n GPS/Navigation L, LT, LTC, LTM and Burst Mode are registered trademarks and Hot Swap and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks are the property of their n Digital Cameras respective owners. Protected by U.S. Patents including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131, 6144194. n PC Cards n Wireless and DSL Modems n General Purpose Point of Load DC/DC OUT2 Efficiency Typical a T (Burst Mode Operation) V IN 2.5V TO 5.5V 100 10 REFER TO FIGURE 4 10F V IN 95 EFFICIENCY FREQ 1 1.5H 2.2H V V OUT1 OUT2 1.8V SW1 SW2 2.5V 22pF 22pF 90 1.5A 1A RUN2 V RUN1 V 0.1 IN IN LTC3417A 85 511k 866k V V FB2 0.01 FB1 80 POWER LOSS 47F 412k 412k 22F I I TH2 TH1 0.001 75 V = 3.6V IN 5.9k 2.87k V = 2.5V GND OUT FREQ = 1MHz 0.0001 2200pF 6800pF 70 0.001 0.01 0.1 1 3417 TA01 LOAD CURRENT (A) 3417 TA01a 3417afc 1 EFFICIENCY (%) ion pplica ions pplica ion uresLTC3417A a Te Maxi Mu M r a T (Note 1) V , V Voltages ...................................... 0.3V to 6V PGOOD Voltage ........................................... 0.3V to 6V IN1 IN2 SYNC/MODE, SW1, SW2, RUN1, Operating Ambient Temperature Range RUN2, V , V , PHASE, FREQ, (Note 2) ..................................................40C to 85C FB1 FB2 I , I Voltages............... 0.3V to (V /V + 0.3V) Junction Temperature (Notes 7, 8) ...................... 125C TH1 TH2 IN1 IN2 V V , V V .......................................... 0.3V Storage Temperature Range ...................65C to 125C IN1 IN2 IN2 IN1 p in c F T TOP VIEW TOP VIEW GNDD 1 20 GNDD RUN1 2 19 PGND1 RUN1 1 16 PGND1 V 3 18 SW1 V 2 15 SW1 IN1 IN1 I 4 17 PHASE I 3 14 PHASE TH1 TH1 V 5 16 GNDA V 4 13 GNDA FB1 FB1 21 17 V 6 15 FREQ V 5 12 FREQ FB2 FB2 I 7 14 PGOOD I 6 11 PGOOD TH2 TH2 RUN2 8 13 SW2 RUN2 7 10 SW2 V 9 12 SYNC/MODE V 8 9 SYNC/MODE IN2 IN2 PGND2 10 11 PGND2 DHC PACKAGE 16-LEAD (3mm 5mm) PLASTIC DFN FE PACKAGE 20-LEAD PLASTIC TSSOP T = 125C, = 43C/W JMAX JA EXPOSED PAD (PIN 17) IS PGND2/GNDD, MUST BE SOLDERED TO PCB T = 125C, = 38C/W JMAX JA EXPOSED PAD (PIN 21) IS PGND2/GNDD, MUST BE SOLDERED TO PCB Der in F Ma T LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3417AEDHC PBF LTC3417AEDHC TRPBF 3417A 16-Lead (3mm 3mm) Plastic DFN 40C to 85C LTC3417AEFE PBF LTC3417AEFE TRPBF LTC3417AEFE 20-Lead Plastic TSSOP 40C to 85C LTC3417AIFE PBF LTC3417AIFE TRPBF LTC3417AIFE 20-Lead Plastic TSSOP 40C to 85C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: