POWER LOSS (W) LTC3600 15V, 1.5A Synchronous Rail-to-Rail Single Resistor Step-Down Regulator Fea T Descrip T n Single Resistor Programmable V The LTC 3600 is a high efficiency, monolithic synchronous OUT n 1% I Accuracy buck regulator whose output is programmed with just one SET n Tight V Regulation Independent of V Voltage external resistor. The accurate internally generated 50A OUT OUT n Easy to Parallel for Higher Current and Heat Spreading current source on the ISET pin allows the use of a single n Wide V Range 0V to V 0.5V external resistor to program an output voltage that ranges OUT IN n High Efficiency: Up to 96% from 0V to 0.5V below V . The V voltage feeds directly IN OUT n 1.5A Output Current back to the error amplifier in unity gain fashion and equals n Adjustable Frequency: 200kHz to 4MHz the ISET voltage. The operating supply voltage range is 4V n 4V to 15V V Range to 15V, making it suitable for dual lithium-ion battery and IN n Current Mode Operation for Excellent Line and Load 5V or 12V input point-of-load power supply applications. Transient Response The operating frequency is synchronizable to an external n Zero Supply Current in Shutdown clock or programmable from 200kHz to 4MHz with an n Available in Thermally Enhanced 12-Pin external resistor. High switching frequency allows the use (3mm 3mm) DFN and MSOP Packages of small surface mount inductors. The unique constant on-time architecture is ideal for operating at high frequency a T in high step-down ratio applications that also demand fast n Voltage Tracking Supplies load transient response. n Point-of-Load Power Supplies L, LT, LTC, LTM, Linear Technology, the Linear logo and OPTI-LOOP are registered trademarks n and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the Portable Instruments property of their respective owners. Protected by U.S. Patents, including 5481178, 5705919, n Distributed Power Systems 5847554, 6580258. Typical a T High Efficiency, 1MHz, 1.5A Step-Down Converter Efficiency and Power Loss vs Output Current 9 LTC3600 100 1.0 V IN BOOST V = 12V IN V IN 0.1F 90 0.9 8 V = 2.5V 12V OUT RUN 50A 80 0.8 DCM POWER 5 + SW 2.2H V 70 LOSS 0.7 OUT PWM CONTROL 10F ERROR 7 2.5V AND SWITCH 60 0.6 AMP 22F DRIVER 50 0.5 CCM 40 0.4 V OUT 30 0.3 11 MODE/ 20 0.2 CCM SYNC INTV RT GND PGFB ITH PGOOD ISET CC 10 0.1 1 6 10 3 13 4 2 12 DCM 3600 TA01a 0 0 0.001 0.01 0.1 1 10 LOAD CURRENT (A) 3600 TA01b 0.1F 1F 49.9k 3600fd 1 EFFICIENCY (%) ion pplica ions pplica ion uresLTC3600 a Te Maxi Mu M r a T (Notes 1, 5) V , SW Voltage ......................................... 0.3V to 16V ITH, RT Voltage .....................................0.3V to INTV IN CC SW Transient Voltage (Note 6) .......................2V to 21V MODE/SYNC, PGFB, PGOOD Voltage ....0.3V to INTV CC V , ISET Voltage ............................................0V to V Operating Junction Temperature Range OUT IN BOOST Voltage ............................0.3V to V + INTV (Notes 2, 5) ............................................ 40C to 125C IN CC RUN Voltage................................................0.3V to 12V MSE Package Lead Temperature INTV Voltage ............................................ 0.3V to 7V (Soldering, 10 sec) ................................................300C CC p in c F T TOP VIEW TOP VIEW 1 12 PGOOD ISET ISET 1 12 PGOOD 2 ITH 11 V OUT ITH 2 11 V OUT 3 13 RT 10 INTV RT 3 13 10 INTV CC CC GND GND PGFB 4 9 BOOST 4 9 BOOST PGFB RUN 5 8 V IN 5 8 V RUN IN MODE/SYNC 6 7 SW 6 7 MODE/SYNC SW MSE PACKAGE DD PACKAGE 12-LEAD PLASTIC MSOP 12-LEAD (3mm 3mm) PLASTIC DFN T = 125C, = 43C/W JMAX JA T = 125C, = 55C/W JMAX JA EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB o r Der i n F Ma T