POWER LOSS (W) LTC3407A-2 Dual Synchronous 800mA, 2.25MHz Step-Down DC/DC Regulator DESCRIPTIO FEATURES High Efficiency: Up to 95% The LTC 3407A-2 is a dual, constant frequency, synchro- Low Ripple (<35mV ) Burst Mode Operation nous step-down DC/DC converter. Intended for low power PK-PK I = 40 A applications, it operates from a 2.5V to 5.5V input voltage Q 2.25MHz Constant Frequency Operation range and has a constant 2.25MHz switching frequency, No Schottky Diodes Required enabling the use of tiny, low cost capacitors and inductors Low R Internal Switches: 0.35 1mm or less in height. Each output voltage is adjustable DS(ON) Current Mode Operation for Excellent Line from 0.6V to 5V. Internal synchronous 0.35 , 1A power and Load Transient Response switches provide high efficiency without the need for Short-Circuit Protected external Schottky diodes. Low Dropout Operation: 100% Duty Cycle A user selectable mode input is provided to allow the user Ultralow Shutdown Current: I <1 A Q to trade-off ripple noise for low power efficiency. Burst Output Voltages from 5V down to 0.6V Mode operation provides the highest efficiency at light Power-On Reset Output loads, while Pulse Skip Mode provides the lowest ripple Externally Synchronizable Oscillator noise at light loads. Optional External Soft-Start 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 U 40A. In shutdown, the device draws <1 A. APPLICATIO S , LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology PDAs/Palmtop PCs Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131. Digital Cameras Cellular Phones Wireless and DSL Modems TYPICAL APPLICATIO 1mm High 2.5V/1.8V at 800mA Step-Down Regulators Efficiency/Power Loss Curve 100 1 V = 2.5V 2.5V IN 90 TO 5.5V 1.8V 80 100k 10F 0.1 RUN/SS2 V RUN/SS1 IN 70 MODE/SYNC POR RESET 60 LTC3407A-2 50 0.01 2.2H 2.2H 40 V = 2.5V V = 1.8V OUT2 OUT1 SW2 SW1 AT 800mA AT 800mA 22pF 22pF 30 0.001 20 V = 3.3V IN Burst Mode OPERATION V 10 V FB1 FB2 NO LOAD ON OTHER CHANNEL 887k 887k GND 0.0001 0 280k 442k 10F 10F 1 10 100 1000 LOAD CURRENT (mA) 3407A2 TA02 3407A2 TA01 3407a2f 1 EFFICIENCY (%) U ULTC3407A-2 ABSOLUTE AXI U RATI GS (Note 1) V Voltage ..................................................0.3V to 6V Operating Temperature Range (Note 2) IN V , V Voltages...................................0.3V to 1.5V LTC3407AE-2 ..................................... 40C to 85C FB1 FB2 RUN/SS1, RUN/SS2 Voltages ..................... 0.3V to V LTC3407AI-2 .................................... 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) LTC3407AEMSE-2 ............................................ 300C LTC3407AIMSE-2 ............................................. 300C PI CO FIGURATIO TOP VIEW TOP VIEW 10 V 1 V FB1 FB2 V 1 10 V FB1 FB2 RUN/SS1 2 9 RUN/SS2 RUN/SS1 2 9 RUN/SS2 11 V 3 8 POR IN V 3 11 8 POR IN SW1 4 7 SW2 SW1 4 7 SW2 MODE/SYNC GND 5 6 GND 5 6 MODE/SYNC MSE PACKAGE 10-LEAD PLASTIC MSOP DD PACKAGE T = 125C, = 45C/W, = 10C/W 10-LEAD (3mm 3mm) PLASTIC DFN JMAX JA JC EXPOSED PAD (PIN 11) IS PGND, MUST BE CONNECTED TO GND T = 125C, = 45C/W, = 10C/W JMAX JA JC EXPOSED PAD (PIN 11) IS PGND, MUST BE CONNECTED TO GND UUW ORDER I FOR ATIO LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3407AEDD-2 PBF LTC3407AEDD-2 TRPBF LDDH 10-Lead (3mm 3mm) Plastic DFN 40C to 85C LTC3407AEMSE-2 PBF LTC3407AEMSE-2 TRPBF LTDDJ 10-Lead Plastic MSOP 40C to 85C LTC3407AIDD-2 PBF LTC3407AIDD-2 TRPBF LDDH 10-Lead (3mm 3mm) Plastic DFN 40C to 125C LTC3407AIMSE-2 PBF LTC3407AIMSE-2 TRPBF LTDDJ 10-Lead Plastic MSOP 40C to 125C LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3407AEDD-2 LTC3407AEDD-2 TR LDDH 10-Lead (3mm 3mm) Plastic DFN 40C to 85C LTC3407AEMSE-2 LTC3407AEMSE-2 TR LTDDJ 10-Lead Plastic MSOP 40C to 85C LTC3407AIDD-2 LTC3407AIDD-2 TR LDDH 10-Lead (3mm 3mm) Plastic DFN 40C to 125C LTC3407AIMSE-2 LTC3407AIMSE-2 TR LTDDJ 10-Lead Plastic MSOP 40C to 125C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: