LTC1649 Datasheet | Linear Technology

LTC1649 3.3V Input High Power Step-Down Switching Regulator Controller Features s s s s DESCRIPTION The LTC®1649 is a high power, high efficiency switching regulator controller optimized for use with very low supply voltages. It operates from 2.7V to 5V input, and provides a regulated output voltage from 1.26V to 2.5V at up to 20A load current. A typical 3.3V to 2.5V application Features efficiency above 90% from 1A to 10A load. The LTC1649 uses a pair of standard 5V logic-level N-channel external MOSFETs, eliminating the need for expensive P-channel or super-low-threshold devices. The LTC1649 shares its internal switching architecture with the LTC1430, and Features the same ±1% line, load and temperature regulation characteristics. Current limit is user-adjustable without requiring an external low-value sense resistor. The LTC1649 uses a 200k Hz switching frequency and voltage mode control, minimizing external ponent count and size. Shutdown mode drops the quiescent current to below 10µA. The LTC1649 is available in the 16-pin narrow SO package. , LTC and LT are registered trademarks of Linear Technology Corporation. s s s s High Power 3.3V to 1.x V-2.x V Switching Regulator Controller: Up to 20A Output All N-Channel External MOSFETs Provides 5V MOSFET Gate Drive with 3.3V Input Constant Frequency Operation Minimizes Inductor Size Excellent Output Regulation: ±1% Over Line, Load and Temperature Variations High Efficiency: Over 90% Possible No Low-Value Sense Resistor Needed Available in 16-Lead SO Package U APPLICATIONS s s s s 3.3V Input Power Supply for Low Voltage Microprocessors and Logic Low Input Voltage Power Supplies High Power, Low Voltage Regulators Local Regulation for Multiple Voltage Distributed Power Systems TYPICAL APPLICATION 3.3V to 2.5V, 15A Converter VIN 3.3V MBR0530 RIMAX 50k Q1, Q2 IRF7801 TWO IN PARALLEL + 1µF CIN 3300µF LEXT- 1.2µH VOUT 2.5V @15A 22Ω PVCC1 PVCC2 G1 1k IFB Q3 IRF7801 R1 12.4k EFFICIENCY (%) G2 VCC LTC1649 FB...