What is wrong with this LCD backlight boost converter circuit
Look at the front page of the data sheet: -



The internal switch that causes the inductor to "charge up" is limited to 250 mA for the TPS61041. This means that going "balls-out", the maximum power that can be taken from the 3.3 volt supply is 0.825 watts. Inefficiencies might mean only 0.75 watts is delivered to the output load.

You want to drive 40 mA at 25 volts and that's a power requirement of 1 watt. Do you see the problem?


  What is wrong with this LCD backlight boost converter circuit


Probably nothing - misapplication is the likely cause of the problem.