
Linear Technology
DESCRIPTION
The LT ®1309 is a 500kHz micropower DC/DC converter for Flash Memory. The regulator features Burst ModeTM operation with a 0.5A, 300mV switch, enabling 85% efficiency at the fixed 12V output. High frequency operation permits the use of small value, and therefore small size,surfacemountinductorsandcapacitors.TheLT1309 comes in an 8-lead SO package allowing extremely compact PC board layouts. These features make the device attractive for PCMCIA cards, cellular phones and other applications where PC board space is limited.
FEATURES
■ 60mA Output Current at 12V from 3V or 5V Supply
■ Shutdown to 9μA
■ VPP VALID Comparator
■ Up to 85% Efficiency
■ Switching Frequency: 500kHz (Typical)
■ Quiescent Current: 650μA
■ Low VCESAT Switch: 300mV at 0.5A (Typical)
■ Soft Start Reduces Supply Current Transients
■ Uses Low Value, Small Size, Surface Mount Inductors
■ Available in 8-Lead SO Package
APPLICATIONS
■ Flash Memory VPP Generators
■ Type II and III PCMCIA Card DC/DC Converters
■ 3V to 12V, 5V to 12V Converters
■ Portable Computers and Instruments
■ Cellular Telephones
■ DC/DC Converter Module Replacements