We often get asked about regulating a 6V battery to 5V, or a lithium cell to 3.3V or similar where the input voltage is either very close or may even swing either side of the desired output voltage.
Conventional answers may include LDO regulators or even just series diodes, but where the input voltage may drop below the required output voltage a switching approach is required.
The obvious solution is a topology which can both boost and buck, but these can be a little more complex than a simple buck or boost converter.
My thought while sleeping was to use an inverting topology to produce a negative voltage from the (presumably isolated) input. This topology allows the negative voltage to vary from zero to higher than the input voltage and is essentially no more difficult to control than a simple buck or boost configuration.
I'm probably not going to recommend this to a beginner, but for my own projects which may be driven from (say) a single LIPO cell, it seems to be a relatively simple solution.
Is there anything I've missed?
Conventional answers may include LDO regulators or even just series diodes, but where the input voltage may drop below the required output voltage a switching approach is required.
The obvious solution is a topology which can both boost and buck, but these can be a little more complex than a simple buck or boost converter.
My thought while sleeping was to use an inverting topology to produce a negative voltage from the (presumably isolated) input. This topology allows the negative voltage to vary from zero to higher than the input voltage and is essentially no more difficult to control than a simple buck or boost configuration.
I'm probably not going to recommend this to a beginner, but for my own projects which may be driven from (say) a single LIPO cell, it seems to be a relatively simple solution.
Is there anything I've missed?
