POWER LOSS (W) LTC3626 20V, 2.5A Synchronous Monolithic Step-Down Regulator with Current and Temperature Monitoring Fea T Descrip T n 3.6V to 20V Input Voltage Range The LTC 3626 is a high efficiency, monolithic synchronous n Wide Output Voltage Range of 0.6V to 97% V Opti- buck regulator using a phase-lockable controlled on-time, IN mized for 0.6V to 6V current mode architecture capable of supplying up to 2.5A n Low R Integrated Switches Provide Up to 95% of output current. The operating supply voltage range is DS(ON) Efficiency 3.6V to 20V, making it suitable for a wide range of power n Up to 2.5A of Output Current supply applications. n Average Input and Output Current Monitoring The operating frequency is programmable from 500kHz to n Programmable Average Input/Output Current Limit 3MHz with an external resistor allowing the use of small n Die Temperature Monitor and Programmable Limit surface mount inductors. For applications sensitive to n Adjustable Switching Frequency: 500kHz to 3MHz switching noise, the LTC3626 can be externally synchro- n External Frequency Synchronization nized over the same frequency range. An internal phase- n Current Mode Operation for Excellent Line and Load locked loop aligns the on-time of the top power MOSFET to Transient Response the internal or external clock. This unique controlled on-time n 0.6V Reference with 1% Accuracy Over Temperature architecture is ideal for high step-down ratio applications n User Selectable Burst Mode Operation or Forced that demand high switching frequencies and fast transient Continuous Operation response. An internal phase lock loop servos the on-time n Short-Circuit Protected of the internal one-shot timer to match the frequency of n Output Voltage Tracking Capability the internal clock or an applied external clock. n Power Good Status Output n The LTC3626 offers two operational modes: Burst Available in Small, Thermally Enhanced, 20-Lead Mode and forced continuous mode to allow the user (3mm 4mm) QFN Package to optimize output voltage ripple, noise and light load a T efficiency for a given application. L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered and Hot n Distributed Power Systems Swap is a trademark of Linear Technology Corporation. All other trademarks are the property n of their respective owners. Protected by U.S. Patents, including 5481178, 5847554, 6580258, Battery-Powered Instruments 6304066, 6476589, 6774611, 5994885. n Point-of-Load Power Supply Efficiency vs Load Current Typical a T 100 V = 3.3V OUT V 90 IN PV IN 3.6V TO 20V SV IN 80 10 47F RUN BOOST 70 LTC3626 0.1F PGOOD 60 1 2.2H V INTV CC OUT 3.3V TRACK/SS SW 50 2.2F 2.5A ITH 47F 115k 40 0.1 MODE/SYNC V ON 22pF TSET 30 IMON FB IN Burst Mode TMON RT 20 0.01 OPERATION 25.5k IMON OUT V = 12V 10 IN 324k SGND PGND 1F 5.1k 3626 TA01 V = 5V IN 0 0.001 1 10 100 1000 10000 LOAD CURRENT (mA) 3626 TA01b 3626fa 1 For more information www.linear.com/LTC3626 EFFICIENCY (%) ion pplica ions pplica ion uresLTC3626 a Te Maxi Mu M r a T p in c F T (Note 1) TOP VIEW PV ........................................................... 0.3V to 22V IN SV ........................................................... 0.3V to 22V IN BOOST .................................................... 0.3V to 25.6V BOOST-SW ................................................ 0.3V to 3.6V 20 19 18 17 INTV ...................................................... 0.3V to 3.6V BOOST 1 16 PV CC IN INTV 2 15 PV ITH, RT, FB .................................0.3V to INTV + 0.3V CC IN CC V 3 14 ON SV 21 IN MODE/SYNC ..............................0.3V to INTV + 0.3V CC PGND TSET 4 13 RUN TRACK/SS, IMON , IMON ...0.3V to INTV + 0.3V IN OUT CC TMON 5 12 RT TSET, TMON ..............................0.3V to INTV + 0.3V CC SGND 6 11 ITH SW, RUN .......................................... 0.3V to V + 0.3V IN 7 8 9 10 PGOOD ....................................................... 0.3V to 22V V ............................................................ 0.3V to 18V ON SW Source Current (DC, Note 2) ..............................2.5A UDC PACKAGE Operating Junction Temperature Range 20-LEAD (3mm 4mm) PLASTIC QFN T = 125C, = 47C/W JMAX JA (Notes 3, 4) ........................................... 40C to 125C EXPOSED PAD (PIN 21) IS PGND, MUST BE SOLDERED TO PCB Storage Temperature Range .................. 65C to 150C o r Der i n F Ma T LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3626EUDC PBF LTC3626EUDC TRPBF LGCC 20-Lead (3mm 4mm) Plastic QFN 40C to 125C LTC3626IUDC PBF LTC3626IUDC TRPBF LGCC 20-Lead (3mm 4mm) Plastic QFN 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. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: