POWER LOSS (mW) LT3470A Micropower Buck Regulator with Integrated Boost and Catch Diodes FEATURES DESCRIPTION n Low Quiescent Current: 35A at 12V to 3.3V The LT 3470A is a micropower step-down DC/DC con- IN OUT n Integrated Boost and Catch Diodes verter that integrates a 440mA power switch, catch diode n Input Range: 4V to 40V and boost diode into low profile 2mm 3mm DFN n 3.3V at 250mA from 4V to 40V Input package. The LT3470A combines Burst Mode and n 5V at 250mA from 5.7V to 40V Input continuous operation to allow the use of tiny inductor n Low Output Ripple: <10mV and capacitors while providing a low ripple output to n <1A in Shutdown Mode loads of up to 250mA. n Output Voltage: 1.25V to 16V With its wide input range of 4V to 40V, the LT3470A can n Hysteretic Mode Control regulate a wide variety of power sources, from 2-cell Li-Ion n Low Ripple Burst Mode Operation at Light Loads batteries to unregulated wall transformers and lead-acid n Continuous Operation at Higher Loads batteries. Quiescent current in regulation is just 35A in 2 n Solution Size as Small as 50mm a typical application while a zero current shutdown mode n Low Profile (0.75mm) 2mm 3mm Thermally disconnects the load from the input source, simplifying Enhanced 8-Lead DFN Package power management in battery-powered systems. Fast cur- n AEC-Q100 Qualified for Automotive Applications rent limiting and hysteretic control protects the LT3470A and external components against shorted outputs, even APPLICATIONS at 40V input. The LT3470A has higher output current and improved start-up and dropout performance compared n Automotive Battery Regulation to the LT3470. n Power for Portable Products All registered trademarks and trademarks are the property of their respective owners n Distributed Supply Regulation n Industrial Supplies n Wall Transformer Regulation TYPICAL APPLICATION Efficiency and Power Loss vs Load Current 90 1000 V = 12V IN V IN 5.7V TO 40V 80 0.22F V BOOST IN 70 100 LT3470A 33H V OUT 60 5V OFF ON SHDN SW 250mA BIAS 50 10 604k 22pF 1% 40 FB 2.2F 22F GND 200k 30 1 1% 3470a TA01a 20 10 0.1 0.1 1 10 100 300 LOAD CURRENT (mA) 3470a TA01b Rev. C 1 Document Feedback For more information www.analog.com EFFICIENCY (%)LT3470A ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW V , SHDN Voltage ................................................... 40V IN BOOST Pin Voltage .................................................. 47V FB 1 8 SHDN BOOST Pin Above SW Pin ........................................ 25V BIAS 2 7 NC 9 FB Voltage .................................................................. 5V BOOST V 3 6 IN BIAS Voltage .............................................................15V SW 4 5 GND SW Voltage ................................................................V IN Maximum Junction Temperature DDB8 PACKAGE 8-LEAD (3mm 2mm) PLASTIC DFN LT3470AE, LT3470AI ........................................ 125C = 80C/W JA EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB LT3470AH ......................................................... 150C Operating Temperature Range (Note 2) LT3470AE ............................................40C to 85C LT3470AI ........................................... 40C to 125C LT3470AH .......................................... 40C to 150C Storage Temperature Range .................. 65C to 150C Lead Temperature (Soldering, 10 sec) ..................300C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3470AEDDB TRMPBF LT3470AEDDB TRPBF LDPR 8-Lead (3mm 2mm) Plastic DFN 40C to 85C LT3470AIDDB TRMPBF LT3470AIDDB TRPBF LDPR 8-Lead (3mm 2mm) Plastic DFN 40C to 125C LT3470AHDDB TRMPBF LT3470AHDDB TRPBF LDPR 8-Lead (3mm 2mm) Plastic DFN 40C to 150C AUTOMOTIVE PRODUCTS** LT3470AEDDB WTRMPBF LT3470AEDDB WTRPBF LDPR 8-Lead (3mm 2mm) Plastic DFN 40C to 85C LT3470AIDDB WTRMPBF LT3470AIDDB WTRPBF LDPR 8-Lead (3mm 2mm) Plastic DFN 40C to 125C LT3470AHDDB WTRMPBF LT3470AHDDB WTRPBF LDPR 8-Lead (3mm 2mm) Plastic DFN 40C to 150C Contact the factory for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Tape and reel specifications. Some packages are available in 500 unit reels through designated sales channels with TRMPBF suffix. Rev. C 2 For more information www.analog.com