Other Parts Discussed in Thread: TPS51125, TAS5162, TAS5518
Hello. I have an issue with LM5116 giving me as thread says low and unstable output voltage. I made my pcb following the schematic from http://www.ti.com/lit/ug/snva285a/snva285a.pdf page 11.
No matter what input voltage I use the output voltage is 7.5V and if I short DEMB resistor then it rises to about 11v. If i connect at the output any load voltage drops down. For example if I attach 60 ohm resistor at the output, voltage drops down to 4V. I did try to check all connections on my pcb and I did double check all resistors, grounds etc and cant find the cause. I did discover that when I touch pin 5 of the IC or RAMP capacitor then it starts to works as it should. The fun part is that I need to touch it with my metal tweezers, if I touch it with anything non conductive it doesn't work. I suppose it react to body capacitance. So I tried to change that capacitor from 330pF to 100pF, 270pF, 480pF, 560pF and there is small difference in output voltage but never got it over 11V