The original, yet still common approach to buck-boost regulation is the SEPIC and flyback topologies. At low to moderate power, they are acceptable solutions but at high output power they become undesirable because of their bulkier size and higher heat dissipation. To improve on that design, a few years ago Linear Technology introduced the first high efficiency, high power and smaller solution, the LTC3780, a true buck-boost DC/DC regulator IC. Like any high-end analog function, the LTC3780 depends on a fine-tuned layout, careful component selection, and deep power supply design knowledge. It also requires several discrete components, as illustrated on the schematic. Most recently, further improvements were made to the buck-boost circuit when Linear Technology introduced the Buck-Boost DC/DC µModule Regulators: the LTM4605, LTM4607, and LTM4609. With over 24 components housed in each µModule device, the layout is comprised of just the µModule, an inductor, and a few output capacitors. This family offers a simple, pin compatible, high efficiency, high power, compact product for buck-boost voltage regulation.