| 摘要 |
<p>A power supply unit comprises a first switching circuit associated with capacitive and/or inductive impedance for generating at an output a DC output voltage, and a second switching circuit for selectively adding at said output a boost current upon sharp current demands from equipment powered by said power supply unit. Said second switching circuit comprises a switch which is connected directly to said output and a comparator for comparing the actual voltage at said output with a reference voltage obtained by lowering and filtering said actual voltage. Noise immunity is improved, i.e. overheating of the second switching circuit due to unnecessary switching is avoided, while the second switching circuit can operate with a variable voltage unit if required. <IMAGE></p> |
