Hi

I am using the following battery charger for my Li-ion battery,
LTC4162_S-3125557.pdf (mouser.co.uk)

These have been designed as small modules, so I can use them in multiple designs.

Previously, they were used with one power source, such as solar, but now I need to add an additional source, which will be 14V DC.

To allow multiple source, i could simply place two diodes, but i guess this would cause a small loss in power.

I was also thinking about using an ideal diode, but I want to explore any other alternatives.

I have a large QTY of FDMC8327L_D-2312740.pdf (mouser.co.uk). Could I use these MOSFET to create some form of switch mechanism for the two power sources?

 

I would use Schottky diodes, if the higher voltage is always given priority.

 

I would use Schottky diodes, if the higher voltage is always given priority.

Would the voltage drop be major issue with the MPPT feature when solar is used.

 

I don’t think the voltage drop would be a problem, but If the MPPT output voltage drops below 14V it would see the power go to zero as the 14V supply took over. No idea what it would do then.

 

We aim to use the following diodes ssb43l.pdf (vishay.com) as we have plenty of them.

Is there a chance of the diode leaking a little current?

 

You can look it up as well as I can.

 

We aim to use the following diodes ssb43l.pdf (vishay.com) as we have plenty of them.

Is there a chance of the diode leaking a little current?

If it is a Schottky diode then it leaks more than a regular Si diode, but it probably isnt enough to bother anything.
Think of it this way ... If you put a 20k resistor across a regular Si diode, that's about the same leakage you'll see with a Schottky diode. The Schottky diode will have lower forward voltage drop though.
The best Schottky diodes I have seen were made by Zetex, which I think is now part of a different company.