On the other hand, a huge external capacitor, usually in the order of microfarad, is employed to ensure that the ultra-high voltage regulator is stable during all load range. This will increase the costs of the application board. 另外,为了保证在高压环境下稳压器的稳定性,常需要大的片外电容,一般在几到几十微法,这样会增加系统的成本。