LTC3308A 5V, 4A Synchronous Step-Down Silent Switcher in 2mm x 2mm LQFN FEATURESDESCRIPTION n High Efficiency: 8mΩ NMOS, 31mΩ PMOS The LTC®3308A is a very small, high efficiency, low n Programmable Frequency to 3MHz noise, monolithic synchronous 4A step-down DC/DC n Tiny Inductor and Capacitors converter operating from a 2.25V to 5.5V input supply. n Peak Current Mode Control Using constant frequency, peak current mode control at n 22ns Minimum On-Time switching frequencies up to 3MHz and minimum on-time n Wide Bandwidth, Fast Transient Response as low as 22ns, this regulator achieves fast transient n Silent Switcher™ Architecture response with small external components. Silent Switcher n Ultralow EMI Emissions architecture minimizes EMI emissions. n Low Ripple Burst Mode® Operation with IQ of 40µA The LTC3308A operates in forced continuous or pulse n Safely Tolerates Inductor Saturation in Overload skip mode for low noise, or low-ripple Burst Mode n VIN Range: 2.25V to 5.5V operation for high efficiency at light loads, ideal for n VOUT Range: 0.5V to VIN battery-powered systems. The IC regulates output n VOUT Accuracy: ±1% Over Temperature Range voltages as low as 500mV. Other features include output n Precision 400mV Enable Threshold overvoltage protection, short-circuit protection, thermal n Shutdown Current: 1µA shutdown, clock synchronization, and up to 100% duty n Power Good, Internal Compensation and Soft Start cycle operation for low dropout. The device is available n Thermally Enhanced 2mm × 2mm LQFN Package in a low profile 12-lead 2mm × 2mm × 0.74mm LQFN n AEC-Q100 Qualified for Automotive Applications package with 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 LossEfficiency and Power LossHigh Efficiency, 2MHz, 1.2V 4A Step-Down Converterin Burst Mode Operationin Burst Mode Operation 100 10 VIN = 2.25V TO 5.5V 90 EFFICIENCY 1µF 1µF 4.7µF 4.7µF 80 1 0201 0201 330nH V POWER LOSS (W) OUT 70 EN V SW IN VIN 1.2V 60 0.1 SW 4A 50 10pF 140k LTC3308A FB 22µF 40 0.01 V x2 EFFICIENCY (%) POWER LOSS IN 100k 30 10nF V MODE/SYNC IN = 3.3V 20 VOUT = 1.2V 0.001 RT AGND fSW = 2 MHz 10 PGND PGOOD 3308A TA01a Murata DFE201612E–R33M 0 0.0001 0.001 0.01 0.1 1 4 fOSC = 2MHz ILOAD (A) 3308A 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