As shown here, the most straightforward way to convert a 12V rail to a lower voltage is with a 1-Stage DC/DC step-down converter. If there are two, three, or four rails, then a similar number of 12V DC/DC converters may be used in this 1-Stage approach. Each converter will need to support an input voltage of at least 12V. This, of course, requires a silicon manufacturing process supporting breakdown voltages to be higher than the supported input voltage. Typically a silicon manufacturing process of 20V or even higher is used for 12V nominal input voltage DC/DC converter devices. The higher the voltage process, the larger the device, due to oxide thickness and space needed between the drain, the source and the gate of transistors inside. The higher breakdown voltage inevitably comes at the cost of die space. Using larger devices to handle higher voltages will eventually lead to a larger total solution size, as well as higher cost. The advantage of an additional conversion stage from 12V to 6V before converting to even lower voltages is to avoid having to use multiple high input voltage regulators. On the right hand side of this slide, the EC2650QI high efficiency Intermediate Bus Converter (IBC) is used to generate a 6V bus, the power loss is minimized on this first conversion stage providing up to 94% peak efficiency. Although efficiency will never be 100% for the first stage, the power loss here can be made up in the subsequent rails where smaller 6V converters are used. Since the input voltage of the downstream voltage regulators is 6V, a low voltage silicon manufacturing process is used, which is generally smaller and less costly than 20V or higher processes. Due to the lower input voltage, each converter can afford to use lower inductance and still maintain a comparable output ripple. As a result, the solution size for each 6V regulator is much smaller vs its 12V counterpart.