LT1110 Datasheet | Linear Technology

LT1110 Micropower DC-DC Converter Adjustable and Fixed 5V, 12V Features s s s DESCRIPTIO s s s s s Operates at Supply Voltages From 1.0V to 30V Works in Step-Up or Step-Down Mode Only Three External Off-the-Shelf ponents Required Low-Battery Detector parator On-Chip User-Adjustable Current Limit Internal 1A Power Switch Fixed or Adjustable Output Voltage Versions Space-Saving 8-Pin Mini DIP or S8 Package The LT1110 is a versatile micropower DC-DC converter. The device requires only three external ponents to deliver a fixed output of 5V or 12V. The very low minimum supply voltage of 1.0V allows the use of the LT1110 in applications where the primary power source is a single cell. An on-chip auxiliary gain block can function as a low battery detector or linear post regulator. The 70k Hz oscillator allows the use of surface mount inductors and capacitors in many applications. Quiescent current is just 300µA, making the device ideal in remote or battery powered applications where current consumption must be kept to a minimum. The device can easily be configured as a step-up or step-down converter, although for most step-down applications or input sources greater than 3V, the LT1111 is remended. Switch current limiting is user-adjustable by adding a single external resistor. Unique reverse battery protection circuitry limits reverse current to safe, nondestructive levels at reverse supply voltages up to 1.6V. APPLICATI s s s s s s s s s Pagers Cameras Single-Cell to 5V Converters Battery Backup Supplies Laptop and Palmtop puters Cellular Telephones Portable Instruments Laser Diode Drivers Hand-Held Inventory puters TYPICAL APPLICATI All Surface Mount Single Cell to 5V Converter SUMIDA CD54-470K 47µH 1 I LIM 1.5V AA CELL- 2 V IN SW1 90 MBRS120T3 5V EFFICIENCY (%) 85 80 75 70 65 60 55 50 0 - TA01 VIN = 1.00V LT1110-5 SENSE 8 SW2 4 GND 5 + 15µF TANTALUM OPERATES WITH CELL VOLTAGE ≥ 1.0V - ADD 10µF DECOUPLING CAPACITOR IF BATTERY...