WWW.Microsemi .COM LX2304 WWW.Microsemi .COM LX7172/72A LX7172/ LX7172A 1.4MHz 1.2A Synchronous Buck Converter TM PRODUCTION DATASHEET D E S C R IP T I ON KE Y FE A T UR ES Input Supply Range: 2.5V to 5.5V The LX7172/72A are 1.4MHz fixed A standard series of inductors are frequency, current-mode, synchronous available from several different Output Adjustable from 0.6V to ~V IN PWM buck (step-down) DC-DC manufacturers optimized for use with the 100% Duty Cycle in Dropout converters, capable of driving a 1.2A load LX7172/72A. This feature greatly Integrated NMOS & PMOS Switches with high efficiency, excellent line and load simplifies the design of switch-mode power Current Mode Control regulation. The devices integrate supplies. 1.2A Maximum Output Current synchronous P-channel and N-channel The converters include standard safety Fixed 1.4MHz Frequency power MOSFET switches with low on- features such as over-current, short-circuit High Efficiency: Up To 95% resistance. They accept an input voltage and thermal shutdown protection. These Built-in Soft-start range from 2.5V to 5.5V and will enter devices are both available in the SOT23-5 100% duty cycle at dropout making them Built-in UV & OT Protection package, the two versions providing ideal for powering portable equipment that Built-in Short Circuit Protection alternative pin out configurations for runs from a single Li-ion battery. RoHS Compliant & Halogen Free maximum flexibility. A P P L IC A T I ONS Datacom Portable Devices Smart Phone IMPORTANT: For the most current data, consult MICROSEMIs website: WWW.Microsemi .COM LX2304 WWW.Microsemi .COM LX7172/72A 72YWL 2AYWL LX7172/ LX7172A 1.4MHz 1.2A Synchronous Buck Converter TM PRODUCTION DATASHEET A A B S OL UTE M A X IMUM R AT I NGS P A C KA GE P I N OUT VIN (Input Pin) ................................................................................................ -0.3V to 6V EN 1 5 FB EN (Enable Pin) .................................................................................... -0.3V to V +0.3V IN SW (Switch Pin) ................................................................................... -0.3V to V +0.3V IN FB (Feedback Pin) ................................................................................ -0.3V to V +0.3V IN GND 2 Maximum Junction Temperature .............................................................................. 150C Storage Temperature Range ....................................................................... -65 C to 150 C SW 3 4 VIN Peak Package Solder Reflow Temperature (40 seconds maximum exposure) .......... 260C Lead Temperature. (Soldering 10 seconds) ............................................................... 260C Notes: Exceeding these ratings could cause damage to the device. All voltages are with respect to GND. Currents are positive into, negative out of specified terminal. These are stress ratings VIN 1 5 SW only and functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions are not implied. Exposure to Absolute Maximum Ratings for extended periods may affect device reliability. GND 2 3 4 FB EN LX7172 = 72YWL LX7172A = 2AYWL SE PACKAGE (Top View) YWL = Year/Week/Lot Code RoHS / Pb-free Matte Tin Pin Finish R E C OMM E NDE D OPE R A T I N G C OND I TI ONS Min Parameters Symbol Max Units Input Voltage VIN 2.5 5.5 V Output Voltage V 0.6 V -0.5V V OUT IN Maximum Output Current I 1.2 A OUT (MAX) Operating Ambient Temperature T -40 85 C A E L E C TR I C AL C HA RA C T E R IS T I CS Unless otherwise specified, the following specifications apply at VIN = V = 3.3V. T = 25C. EN A Parameters Symbol Test Conditions/Comments MIN TYP MAX Units Operating Current Quiescent Current I V = 0.65V 62 100 A Q FB Shutdown Supply Current I V = GND 0.1 1 A SHDN EN V UVLO IN Under Voltage Lockout V VIN Rising 2.3 V UVLO UVLO Hysteresis V 200 mV HYS Feedback Voltage Feedback Voltage V 0.588 0.6 0.612 V REF Copyright 2013 Page 2 Microsemi Rev. 1.2 07-18-2013 Analog Mixed Signal Group One Enterprise, Aliso Viejo, CA. 92656 USA, 1-800-713-4113, 949-380-6100, Fax: 949-215-4996