| 摘要 |
A DC/DC converter combines elements of a boost and a buck converter with synchronous switching and a single controller to provide a step-up or step-down regulator with continuous input and output currents. A boost converter composed of an inductor in series with the input, a switch to ground, and a diode to an intermediate voltage node provides an intermediate voltage that is greater than the input voltage. A buck converter composed of a switch in series with the intermediate voltage node, a diode to ground, and an inductor in series with the output provides an output voltage that is less than the intermediate voltage. The output is regulated by a single pulse width modulating controller which drives the boost switch and buck switch simultaneously. This technique provides a DC/DC converter that can operate with an input voltage greater than or less than the output voltage. Further, series inductance on both input and output nodes provides continuous input and output AC current reducing conducted noise effects. Further, the input and output inductors have equivalent volt-second characteristics allowing for the possibility to couple the input and output inductors on a single magnetic element. An isolated form of the invention is possible by replacing the buck stage with a transformer-isolated forward converter.
|
