Datasheet and Circuit Diagram, Posted by: admindata at August 31st, 2009
If you need to construct a simple DC/DC Converter which can deliver 5V at 100mA from 3V input or 12 V at 60 mA from a 5V input, you may consider the LT1109 IC series from Linear Technology. It is available in 8-pin version features a logic controlled shutdown pin that turns off the oscillator when taken low.
The circuit diagram performs the typical application of this device. According to datasheet, another feature of LT1109 are uses Off-the-Shelf Inductors, require only 33uH inductor, 120 KHz Oscillator, only three external components needed to design a complete DC/DC converter device, and 1.6V minimum start-up voltage. Therefore, this IC can be applied in battery powered equipment, 3-5V Converter or 5V-12V Converters, Flash memory VPP generators, peripherals, disk drives and etc.
Please see more about The LT1109 Step-Up DC/DC Converter in LT1109 Datasheet, and see circuit diagrams such bootstrapping circuit operation, 3V to 5V Converter with Shutdown, and 3-Pin Package Flash Memory VPP Generator.