| 摘要 |
<p>For use in a boost converter (200) having a boost inductor (205) coupled between an input and an output of the boost converter and an output capacitor (208) coupled between rails (OR1, OR2) of the output, an energy storage circuit for, and method of, extending a holdup time of the boost converter. In one embodiment, the energy storage circuit includes: (1) a holdup capacitor (209) coupled to a first rail (IR2) of the input, (2) a holdup switch (210), coupled to a second rail (IR1) of the input and the holdup capacitor, capable of closing during a holdup mode to allow the holdup capacitor to discharge current into the input, and (3) a voltage stabilizing circuit, (211, 212), coupled between the holdup capacitor and the output capacitor, that: (3a) when the boost converter is in a normal mode, provides a substantially impeded path for charge current to flow from the output capacitor (208) to charge the holdup capacitor (209), and (3b) when the boost converter is in an initial phase of the holdup mode, provides a substantially unimpeded path for holdup current to flow from the holdup capacitor (209) to the output capacitor (208) prior to the closing of the holdup switch (210). <IMAGE></p> |
