The LT1108 is a versatile micropower DC/DC converter. The device requires only four external components to deliver a fixed output of 5V or 12V. Supply voltage ranges from 2V to 12V in step-up mode and to 30V in step-down mode.The LT1108 functions equally well in step-up,step-down, or inverting applications. The LT1108 is pin-for-pin compatible with the LT1173,but has a duty cycle of 70%, resulting in increased outputcurrent in many applications. The LT1108 can deliver 150mA at 5V from a 2 AA cell input and 5V at 300mA from 9V in step-down mode. Quiescent current is just 110µA,making the LT1108 ideal for power conscious battery-operated systems. Switch current limit can be programmed with a single resistor.An auxiliary gain block can be configured as a low battery detector, linear post regulator, under voltage lock-out circuit, or error amplifier.
