LTC1626 Datasheet | Linear Technology

LTC1626 Low Voltage, High Efficiency Step-Down DC/DC Converter Features s s s s DESCRIPTION The LTC ®1626 is a monolithic, low voltage, step-down current mode DC/DC converter featuring Burst Mode TM operation at low output current. The input supply voltage range of 2.5V to 6V makes the LTC1626 ideal for single cell Li-Ion and 3- or 4-cell Ni Cd/ Ni MH applications. A built-in 0.32Ω switch (VIN = 4.5V) allows up to 0.6A of output current. The LTC1626 incorporates automatic power saving Burst Mode operation to reduce gate charge losses when the load current drops below the level required for continuous operation. With no load, the converter draws only 165µA. In shutdown, it draws a mere 0.5µA- making it ideal for current sensitive applications. The inductor current is user-programmable via an external current sense resistor. In dropout, the internal P-channel MOSFET switch is turned on continuously, maximizing battery life. s s s s s s s Wide Input Supply Voltage Range: 2.5V to 6V High Efficiency: Up to 95% Low RDS(ON) Internal Switch: 0.32Ω (VIN = 4.5V) Current Mode Operation for Excellent Line and Load Transient Response Short-Circuit Protected Low Dropout Operation: 100% Duty Cycle Built-In Low-Battery Detector Low Quiescent Current at Light Loads: IQ = 165µA Ultralow Shutdown Current: IQ = 0.5µA Peak Inductor Current Independent of Inductor Value Available in 14-Pin SO Package U APPLICATIONS s s s s s s s Single Cell Li-Ion Step-Down Converters 3- or 4-Cell Ni MH Step-Down Converters Cellular Telephones 5V to 3.3V Conversion 3.3V to 2.5V Conversion Inverting Converters Portable Instruments , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. TYPICAL APPLICATION VIN 2.7V TO 6V + CIN† 47µF 16V 0.1µF PWR VIN SHDN LTC1626 VIN SW PGND ITH CT SENSE + SENSE - SGND VFB 100p F 10k 1626 F01 L- 33µH D1 MBRS130LT RSENSE- - 0.1Ω VOUT 2.5V 0.25A 3900p F 470Ω + COUT†† 100µF...