POWER LOSS (W) LTC3417A-2 Dual Synchronous 1.5A/1A 4MHz Step-Down DC/DC Regulator FEATURES DESCRIPTION n High Ef ciency: Up to 95% The LTC 3417A-2 is a dual constant frequency, synchro- n 1.5A/1A Guaranteed Minimum Output Current nous step-down DC/DC converter. Intended for medium n Synchronizable to External Clock power applications, it operates from a 2.25V to 5.5V input n No Schottky Diodes Required voltage 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 Ripple (<35mV ) BurstMode Operation is adjustable from 0.8V to 5V. Internal synchronous, low P-P I : 125A in Sleep R power switches provide high ef ciency without DS(ON) Q n Low R Internal Switches the need for external Schottky diodes. DS(ON) n Short-Circuit Protected A user selectable mode input allows the user to trade n V : 2.25V to 5.5V IN off ripple voltage for light load ef ciency. Burst Mode n Current Mode Operation for Excellent Line and Load operation provides high ef ciency at light loads, while Transient Response Pulse Skip mode provides low ripple noise at light loads. n Ultralow Shutdown Current: I < 1A Q A phase mode pin allows the second channel to operate n Low Dropout Operation: 100% Duty Cycle in-phase or 180 out-of-phase with respect to channel 1. n Power Good Ouput Out-of-phase operation produces lower RMS current on n Phase Pin Selects 2nd Channel Phase Relationship V and thus lower stress on the input capacitor. IN with Respect to 1st Channel n To further maximize battery life, the P-channel MOSFETs Internal Soft-Start with Individual Run Pin Control n are turned on continuously in dropout (100% duty cycle) Available in Small Thermally Enhanced and both channels draw a total quiescent current of only (5mm 3mm) DFN and 20-Lead TSSOP Packages 100A. In shutdown, the device draws <1A. APPLICATIONS L, LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents n GPS/Navigation Systems including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131, 6144194. n Automotive Instrumentation n PC Cards n Industrial Power Supplies n General Purpose Point of Load DC/DC V Ef ciency OUT2 TYPICAL APPLICATION (Burst Mode Operation) 100 10 V IN REFER TO FIGURE 4 2.5V TO 5.5V 10F V IN 95 EFFICIENCY 1 FREQ 1.5H 2.2H V V OUT1 OUT2 90 1.8V SW2 2.5V SW1 0.1 22pF 22pF 1.5A 1A RUN2 V RUN1 V IN IN 85 LTC3417A-2 0.01 511k 866k V V FB2 FB1 80 POWER LOSS 47F 412k 412k 22F 0.001 75 V = 3.6V I IN I TH2 TH1 V = 2.5V OUT 5.9k 2.87k FREQ = 1MHz GND 0.0001 70 0.001 0.01 0.1 1 2200pF 6800pF LOAD CURRENT (A) 3417A-2 TA01 3417A-2 TA01a 3417a2fa 1 EFFICIENCY (%)LTC3417A-2 ABSOLUTE MAXIMUM RATINGS (Note 1) PGOOD Voltage ........................................... 0.3V to 6V V , V Voltages ...................................... 0.3V to 6V IN1 IN2 Operating Temperature Range (Note 2) SYNC/MODE, SW1, SW2, RUN1, LTC3417AE-2 ....................................... 40C to 85C RUN2, V , V , PHASE, FREQ, FB1 FB2 LTC3417AI-2 ...................................... 40C to 125C I , I Voltages......... 0.3V to ((V or V )+ 0.3V) TH1 TH2 IN1 IN2 Junction Temperature (Notes 7, 8) ...................... 125C V V , V V .......................................... 0.3V IN1 IN2 IN2 IN1 Storage Temperature Range ................... 65C to 150C PIN CONFIGURATION 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 T = 125C, = 38C/ W JMAX JA MUST BE SOLDERED TO PCB EXPOSED PAD (PIN 21) IS PGND2/GNDD MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3417AEDHC-2 PBF LTC3417AEDHC-2 TRPBF 3417A2 16-Lead (3mm 5mm) Plastic DFN 40C to 85C LTC3417AIDHC-2 PBF LTC3417AIDHC-2 TRPBF 3417A2 16-Lead (3mm 5mm) Plastic DFN 40C to 125C LTC3417AEFE-2 PBF LTC3417AEFE-2 TRPBF LTC3417AFE-2 20-Lead Plastic TSSOP 40C to 85C LTC3417AIFE-2 PBF LTC3417AIFE-2 TRPBF LTC3417AFE-2 20-Lead Plastic TSSOP 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: