Hello!

I have this project of a power path for switching between 14V Li-Ion and 12VDC wall power supply. The reason I need a controller is I want to always prioritizer the 12V, no matter what voltage the battery is (basic diode would prioritize higher voltage)

After working on the Demo Circuit of the LTC4416, I had great results for my application. Switching was working great.

So I decided to go on with LTC 4416 and make a PCB. For some reason, the switching is not occurring on my PCB, and I can’t find the reason why! I reviewed everything for the 10th times and still don’t find why it’s not working!

Here is the original LTC4416 for my application (14V battery and 12V power supply with priority to the 12VDC.)


Here is my PCB circuit ;

I am using the same MOSFET as the Demo Board. I just can’t find what is wrong.

Did I missed anything ?!!?

 

The first schematic resistors are 1000X the resistance of the second circuit. Did the low value resistors burn and open? The power dissipation of the 158 ohm is just about 1 watt.