convert negative to positive voltage regulator
Dear All,
The normal regulator only converts the positive voltage and their substrate is ground.
Now I want to design a regulator, whose negative input voltage may exceed its negative substrate voltage.
For example, its input voltage is from -10V to +10V, I would like to convert it to constant voltage -5V to +5V. But the chip substrate is -5V. Of course, the ground is also available.
Usually, the chip substart should be connected to the most negative voltage potential, but in this case, when there is -10V at the input, the substrate is not the lowest potential for the whole chip any more.
Therefore, I would like to solve this problem and search for the design method of the regulator, or are there any papers on such kind of regulator?
thanks!