SC1633

LOW VOLTAGE STEP-UP DC-DC CONVERTER January 29, 1998 SC1633 TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com DESCRIPTION The SC1633 is a high efficiency step up DC-DC converter. Only four external components are required to deliver a fixed voltage of 3V, 3.3V, or 5V. Efficiency beyond 83% can be easily achieved at 70mA load with 2.2V to 3V input voltages. A logic-controlled shutdown mode is provided for power saving. Switch current limit can be programmed with a resistor. The low battery detector can be configured as a linear regulator or a burst mode controller providing extremely low supply current operation. A switching rate of 120kHz reduces the inductor size inductors of 47µH to 150µH inductance are recommended for most applications. FEATURES High efficiency 87% Power-saving shutdown mode (7µA typical) Internal 0.8A switch 120kHz switching rate Adjustable switch current limit On-chip low battery detector APPLICATIONS Pocket organizers Electronic dictionaries Cameras Pagers Bar code scanners LCD displays Battery backup supplies Portable instruments ORDERING INFORMATION BLOCK DIAGRAM DEVICE (1) VOLTAGE 3.3V 3.0V 5.0V PACKAGE SO-8 SC1633CS SC1633-3CS SC1633-5CS Note: (1) Add suffix ‘TR’ for tape and reel. ABSOLUTE MAXIMUM RATINGS Parameter Supply Voltage Operating Temperature Range Storage Temperature Range Symbol VIN TA TSTG Maximum 7.0 0 to 70 -65 to 125 Units V °C °C PIN CONFIGURATION TYPICAL APPLICATION CIRCUIT © 19...