Hi. I hope this is the correct forum to post this in, but I wondered if anyone has any suggestions as i'm struggling to find a DC-DC buck that matches the below characteristics:

- Input Voltage will be between 4.2V-3V (Lithium-ion Battery)
- My desired output Voltage is 2.5V (this is normally adjustable with resistors)
- Output current rating needs to be 8A or higher. (at 2.5V the load will be ~6A)

its basically to take a lithium battery voltage, and give a 2.5V rail

thanks in advance

 

Not surprising because the MOSFET switch is likely to need more than 3V. I can find some that go down to 4V, but no lower.

I would look into building your own with a BJT switch, or a very specialized low Vgs threshold MOSFET.

 

2264
TI
AD
There are probably 100 ICs that will do this job.

 

If you look closely, they can take an input voltage below 3V but they need an additional 3.3V or 5V “ bias” supply for the logic.