How to convert 3.0 VDC to 400 VDC?

I’m using a small energy harvesting circuit to charge a small rechargeable lithium-ion cell (LIR2032). The operating voltage range of the cell will be 3.0V - 4.0V. I’m looking to boost up this voltage to 400 VDC. I cannot simply find a boost converter which converts 3.0V to 400V. Perhaps two boost converters can be cascaded: 3V → intermediate high voltage → 400V. I am looking for engineering advice/solutions as to how I can convert 3.0VDC to 400 VDC. Thanks!


Use of a purpose-built converter such as the Q05-5 would seem the most direct/convenient approach. If rolling one’s own, something based on a flyback converver or voltage multiplier circuit might be a thing to consider.

Do pay attention to your current requirements at various stages, as LIR2032s don’t have much to offer and demands escalate quickly when contemplating a 130x step-up ratio.