LTC7151S 20V, 15A Synchronous Step-Down Silent Switcher 2 Regulator FEATURESDESCRIPTION n Silent Switcher ® 2 Architecture for Low EMI The LTC®7151S is a high efficiency monolithic synchro- n VIN Range: 3.1V to 20V nous buck regulator capable of delivering 15A to the load. n VOUT Range: 0.5V to 5.5V It uses a phase lockable controlled on-time constant fre- n Differential VOUT Remote Sense quency, current mode architecture. PolyPhase operation n Adjustable Frequency: 400kHz to 3MHz allows multiple LTC7151S regulators to run out-of-phase, n PolyPhase® Operation: Up to 12 Phases which reduces the amount of input and output capacitors n Output Tracking and Soft-Start required. The operating supply voltage range is from 3.1V n Reference Accuracy: ±1% Overtemperature to 20V. n Current Mode Operation for Excellent Line and Load The operating frequency is programmable from 400kHz Transient Response to 3MHz with an external resistor. The high frequency n Accurate 1.2V Run Pin Threshold capability allows the use of physically smaller inductor n Supports Forced Continuous/Discontinuous Modes and capacitor sizes. For switching noise sensitive applica- n 28-Lead Thermally Enhanced 4mm × 5mm × tions, the LTC7151S can be externally synchronized from 0.74mm LQFN Package 400kHz to 3MHz. The PHMODE pin allows the user control of the phase of the outgoing clock signal. The unique con- APPLICATIONS stant frequency/controlled on-time architecture is ideal for high step-down ratio applications that operate at high n Automotive and Industrial Power Supplies frequencies while demanding fast transient response. The n Server Power Applications LTC7151S uses second generation Silent Switcher 2 tech- n Distributed Power Systems nology including integrated bypass capacitors to deliver a n Point-of-Load Supply for ASIC, FPGA, DSP, µP, etc. highly efficient solution at high frequencies with excellent All registered trademarks and trademarks are the property of their respective owners. EMI performance. TYPICAL APPLICATION12VIN to 1.0VOUT ApplicationEfficiency and Power LossEfficiency and Power Loss 0.25µH 100 6 VIN SV RUN SW VOUT IN = 5V, PVIN = 12V 3.1V TO 20V 1.0V/15A f 22µF 10k SW = 1MHz PV 95 5 IN FB + ×2 100µF SV ×2 330µF IN LTC7151S 10k POWER LOSS (W) 90 4 PHMODE V – OUT TRACK/SS PGOOD 85 3 CLKOUT MODE/SYNC EFFICIENCY (%) 80 2 INTVCC GND RT ITH 4.7µF 75 1 7151S TA01a 162k 10k 22pF 70 0 0 3 6 9 12 15 1nF IOUT (A) 7151S TA01b Rev. 0 Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Electrical Characteristics Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Typical Applications Package Photo Typical Application Related Parts
