Hello, i write here because i am having some trouble with a LM20124, i know it`s not dificult in theory to make it work , just with select the proper components, but i have made a board and didnt work out. I have two questions related to it, before write in this forum I was looking for and answer of why didn`t work and got to interesting things of why may be its not working.
First of all i was looking at the datasheet and it`s says that pin 16 is N/C no connection, but looking at the pdf "AN-1654 LM20124 Evaluation Board (Rev. B)" on board layout page it`s tied up to ground. I really dont know if that conecction to ground can make the ic to not funtion at all, or even make some damage to the ic just as the problem i have that make my entry source goes down and current to sink as if i have a shortcut in some place. ( Just to write, i have checked that all pins are not shortcircuiting )
My second question , its about i was traying to make something similar to what was made on "High Efficiency Portable Media Player (PMP) Dock Station User Guide" snlu068.pdf (page 3) , all because my proyect needs a two powers +3.3V and 5 v and and input that can change fron 3.7v a (li ion batery) to +5v and output current can change from 10 mA to 600 mA. I was realy wondering if it really can be done because on datasheet saids maximum duty cycle it would be 85% and if i put a 3.7V li ion batery on its entry duty cycle it would be D= Vo/Vi -> D=3.3/3.7 equals 90% or also it can be done because of that small small current of 10mA.
If someone can aswer me maybe why its not working and if have and idea if its possible to implement it. I would be vaery grateful. :)
