CD43-4R7

LT1945 Dual Micropower DC/DC Converter with Positive and Negative Outputs FEATURES s s DESCRIPTIO s s s s s U APPLICATIO S s s s s Generates Well-Regulated Positive and Negative Outputs Low Quiescent Current: 20µA in Active Mode (per Converter) <1µA in Shutdown Mode Operates with VIN as Low as 1.2V Low VCESAT Switch: 250mV at 300mA Uses Small Surface Mount Components High Output Voltage: Up to ±34V Tiny 10-Pin MSOP Package Small TFT LCD Panels Handheld Computers Battery Backup Digital Cameras The LT®1945 is a dual micropower DC/DC converter in a 10-pin MSOP package. Each converter is designed with a 350mA current limit and an input voltage range of 1.2V to 15V, making the LT1945 ideal for a wide variety of applications. Both converters feature a quiescent current of only 20µA at no load, which further reduces to 0.5µA in shutdown. A current limited, fixed off-time control scheme conserves operating current, resulting in high efficiency over a broad range of load current. The 36V switch allows high voltage outputs up to ±34V to be easily generated without the use of costly transformers. The LT1945’s low off-time of 400ns permits the use of tiny, low profile inductors and capacitors to minimize footprint and cost in space-conscious portable applications. , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATIO VIN 2.7V TO 5V L1 10µH 8 VIN 2 C1 4.7µF SHDN1 LT1945 4 SHDN2 3 7 9 FB2 6 Dual Output (+12V, –20V) Converter C4 0.1µF 10 SW1 NFB...