Just a note to those who would like to do some research. Mexico's standard voltage is 127 volts. Not 120 like Canada or the US.
Everyone who has low voltage problems in Mexico has a real problem since it is regulated 7 volts higher than the US from the source.
I sit at about 133 volts with no or a dozen RV's running AC's.Well within range of a + or - of 5% and pretty standard in the industry.
Your laptop power supply is able to run from 100 to 200 volts, plus or minus. Look at the label. The circuit boards runs on anywhere, depending on the design, from 3 volts to 9 volts and most in the mid range. It has always seemed to me that the problem is the RV industry ( and vendor to them) is the problem. They won't build a power supply like your laptop has, the size of a half a pack of cigarettes, that handles any voltage. They would rather sell new circuit boards at 100 dollars a pop and make money.