LTC3309A 5V, 6A Synchronous Step-Down Silent Switcher in 2mm x 2mm LQFN FEATURESDESCRIPTION n High Efficiency: 8mΩ NMOS, 31mΩ PMOS The LTC®3309A is a very small, high efficiency, low noise, n Programmable Frequency to 3MHz monolithic synchronous 6A step-down DC/DC converter n Tiny Inductor and Capacitors operating from a 2.25V to 5.5V input supply. Using con- n Peak Current Mode Control stant frequency, peak current mode control at switching n 22ns Minimum On-Time frequencies up to 3MHz and minimum on-time as low as n Wide Bandwidth, Fast Transient Response 22ns, this regulator achieves fast transient response with n Silent Switcher™ Architecture small external components. Silent Switcher architecture n Ultralow EMI Emissions minimizes EMI emissions. n Low Ripple Burst Mode® Operation with IQ of 40µA The LTC3309A operates in forced continuous or pulse n Safely Tolerates Inductor Saturation in Overload skip mode for low noise, or the low-ripple Burst Mode n VIN Range: 2.25V to 5.5V operation for high efficiency at light loads, ideal for bat- n VOUT Range: 0.5V to VIN tery-powered systems. The IC regulates output voltages n VOUT Accuracy: ±1% Over Temperature Range as low as 500mV. Other features include output over- n Precision 400mV Enable Threshold voltage/short-circuit protection, thermal shutdown, clock n Shutdown Current: 1µA synchronization, and up to 100% duty cycle operation n Internal Compensation and Soft Start for low dropout. The device is available in a low profile n Power Good Output 12-lead 2mm × 2mm × 0.74mm LQFN package with n Thermally Enhanced 2mm × 2mm LQFN Package exposed pad for low thermal resistance. APPLICATIONS All registered trademarks and trademarks are the property of their respective owners. n Optical Networking, Servers, Telecom n Automotive, Industrial, Communications n Distributed DC Power Systems (POL) n FPGA, ASIC, µP Core Supplies TYPICAL APPLICATIONEfficiency and Power LossHigh Efficiency, 2MHz, 1.2V 6A Step-Down Converterin Burst Mode Operation 100 10 VIN = 2.25V TO 5.5V 90 EFFICIENCY 0.1µF 0.1µF 80 1 10µF 10µF 0201 0201 220nH POWER LOSS (W) V 70 OUT EN V SW IN VIN 1.2V 60 0.1 SW 6A 50 6.8pF 140k 0.01 LTC3309A FB 33µF 40 x2 EFFICIENCY (%) POWER LOSS 100k 30 V MODE/SYNC IN = 3.3V 20 V 0.001 OUT = 1.2V RT AGND fSW = 2 MHz 10 PGND PGOOD 3309A TA01a COILCRAFT XEL3515–221 0 0.0001 0.001 0.01 0.1 1 6 fOSC = 2MHz LOAD CURRENT (A) 3309A TA01b Rev. 0 Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts
