POWER LOSS (W) LTC3407A Dual Synchronous 600mA, 1.5MHz Step-Down DC/DC Regulator FEATURES DESCRIPTION n High Ef ciency: Up to 96% The LTC 3407A is a dual, constant frequency, synchronous n Low Ripple (35mV ) Burst Mode Operation step-down DC/DC converter. Intended for low power ap- P-P I = 40A plications, it operates from a 2.5V to 5.5V input voltage Q n 1.5MHz Constant Frequency Operation range and has a constant 1.5MHz switching frequency, n No Schottky Diodes Required enabling the use of tiny, low cost capacitors and inductors n Low R Internal Switches: 0.35 1mm or less in height. Each output voltage is adjustable DS(ON) n Current Mode Operation for Excellent Line from 0.6V to 5V. Internal synchronous 0.35, 1A power and Load Transient Response switches provide high ef ciency without the need for n Short-Circuit Protected external Schottky diodes. n Low Dropout Operation: 100% Duty Cycle A user selectable mode input is provided to allow the user n Ultralow Shutdown Current: I < 1A Q to trade-off ripple noise for low power ef ciency. Burst n Output Voltages from 5V down to 0.6V Mode operation provides the highest ef ciency at light n Power-On Reset Output loads, while Pulse Skip Mode provides the lowest ripple n Externally Synchronizable Oscillator noise at light loads. n Optional External Soft-Start n To further maximize battery life, the P-channel MOSFETs Small Thermally Enhanced MSOP and 3mm 3mm are turned on continuously in dropout (100% duty cycle), DFN Packages and both channels draw a total quiescent current of only 40A. 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 PDAs/Palmtop PCs including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131. n Digital Cameras n Cellular Phones n Wireless and DSL Modems TYPICAL APPLICATION 1mm High 2.5V/1.8V at 600mA Step-Down Regulators LTC3407A Ef ciency/Power Loss Curve 100 1 V = 2.5V 2.5V IN 90 TO 5.5V 1.8V 80 10F 100k 0.1 RUN/SS2 V RUN/SS1 IN 70 MODE/SYNC POR RESET 60 LTC3407A 50 0.01 2.2H 2.2H 40 V = 2.5V V = 1.8V OUT2 OUT1 SW2 SW1 AT 600mA AT 600mA 22pF 22pF 30 0.001 20 V = 3.3V IN Burst Mode OPERATION V V FB1 10 FB2 NO LOAD ON OTHER CHANNEL 887k 887k GND 0.0001 0 280k 442k 10F 10F 1 10 100 1000 LOAD CURRENT (mA) 3407A TA02 3407A TA01 3407afa 1 EFFICIENCY (%)LTC3407A (Note 1) ABSOLUTE MAXIMUM RATINGS V Voltage ...................................................0.3V to 6V Operating Temperature Range (Note 2) IN V , V Voltages ................................... 0.3V to 1.5V LTC3407AE .......................................... 40C to 85C FB1 FB2 RUN/SS1, RUN/SS2 Voltages ......................0.3V to V LTC3407AI ......................................... 40C to 125C IN MODE/SYNC Voltage ....................................0.3V to V Junction Temperature (Note 5) ............................. 125C IN SW1, SW2 Voltages ......................... 0.3V to V + 0.3V Storage Temperature Range ................... 65C to 150C IN POR Voltage ................................................. 0.3V to 6V Lead Temperature (Soldering, 10 sec) LTC3407AMSE Only .......................................... 300C PIN CONFIGURATION TOP VIEW TOP VIEW V 1 10 V FB1 FB2 V 1 10 V FB1 FB2 RUN/SS1 2 9 RUN/SS2 RUN/SS1 2 9 RUN/SS2 V IN 11 V 3 11 8 POR 3 8 POR IN SW1 4 7 SW2 SW1 4 7 SW2 MODE/ GND 5 6 GND SYNC 5 6 MODE/ SYNC MSE PACKAGE 10-LEAD PLASTIC MSOP DD PACKAGE 10-LEAD (3mm 3mm) PLASTIC DFN EXPOSED PAD IS PGND (PIN 11) MUST BE CONNECTED TO GND EXPOSED PAD IS PGND (PIN 11) T = 125C, = 45C/W, = 10C/W JMAX JA JC MUST BE CONNECTED TO GND T = 125C, = 45C/W, = 10C/W JMAX JA JC ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3407AEDD PBF LTC3407AEDD TRPBF LCQN 10-Lead (3mm 3mm) Plastic DFN 40C to 85C LTC3407AIDD PBF LTC3407AIDD TRPBF LCQN 10-Lead (3mm 3mm) Plastic DFN 40C to 125C LTC3407AEMSE PBF LTC3407AEMSE TRPBF LTCRZ 10-Lead Plastic MSOP 40C to 85C LTC3407AIMSE PBF LTC3407AIMSE TRPBF LTCRZ 10-Lead Plastic MSOP 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: