LTC3603IUF

FEATURES n n n n n n n n n n n n n LTC3603 2.5A, 15V Monolithic Synchronous Step-Down Regulator DESCRIPTION The LTC®3603 is a high efficiency, monolithic synchronous step-down DC/DC converter utilizing a constant-frequency, current mode architecture. It operates from an input voltage range of 4.5V to 15V and provides an adjustable regulated output voltage from 0.6V to 14.5V while delivering up to 2.5A of output current. The internal synchronous power switch with 45mΩ on-resistance increases efficiency and eliminates the need for an external Schottky diode. The switching frequency can either be set by an external resistor or synchronized to an external clock. OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of loads and output capacitors. The LTC3603 can be configured for either Burst Mode operation or forced continuous operation. Forced continuous operation reduces noise and RF interference, while Burst Mode operation provides the highest efficiency at light loads. In Burst Mode operation, external control of the burst clamp level allows the output voltage ripple to be adjusted according to the requirements of the application. L, LT, LTC, LTM, Burst Mode, OPTI-LOOP Linear Technology and the Linear logo are registered , trademarks and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 6580258, 6498466, 6611131, 6177787, 5705919, 5847554. Wide Input Voltage Range: 4.5V to 15V 2.5A Output Current Low RDS(ON) Internal Switches: 45mΩ and 85mΩ Programmable Frequency: 300kHz to 3MHz Low Quiescent Current: 75μA 0.6V ±1% Reference Allows Precise, Low Output Voltage 99% Maximum Duty Cycle Adjustable Burst Mode® Clamp Synchronizable to External Clock Power Good Output Voltage Monitor Overtemperature Protection Overvoltage Protection Available in 16-Lead Thermally Enhanced MSOP and 4mm × 4mm QFN Packages APPLICATIONS n n n Point-of-Load Supplies Portable Instruments Communications Infrastructure TYPICAL APPLICATION 3.3V, 2.5A, 1MHz Step-Down Regulator VIN 4.5V TO 15V 22μF PVIN INTVCC RUN RT 105k 4.32k ITH 1nF PGND 475k 10pF 3603 TA01 Efficiency and Power Loss vs Load Current 100 95 VIN = 12V EFFICIENCY 1000 POWER LOSS (mW) 10000 1μF 90 EFFICIENCY (%) 0.22μF 2.2μH SW 85 80 75 BOOST LTC3603 VOUT 3.3V 100μF 2.5A 100 POWER LOSS PGOOD TRACK/SS 70 65 60 0.001 0.01 0.1 1 LOAD CURRENT (A) 10 SYNC/MODE VFB 105k 1 10 3603 TA01b 3603fa 1 LTC3603 ABSOLUTE MAXIMUM RATINGS (Note 1) PVIN Supply Voltage (DC) .......................... –0.3V to 16V PVIN Supply Transient Voltage (