Are there any simple DC/DC converters that can produce equal +- rails from a single supply? Looking to take anywhere from 3V to 30V and produce a variable + and - from 3V to 30V. I'm looking more for a simple monolithic IC that is efficient for small current draws between 1mA and 50mA.
I've seen a few negative rail generator IC's but they are extremely inefficient at low currents(20-30% at 1mA). Since this is a battery supplied circuit I'd like to make it as efficient as possible.