MP2759 / MP2759A Power dissipation calculation

Battery Management
1

Dear MPS experts,

Can you suggest some equations to calculate the power dissipation of the MP2759A / MP2759 IC during the following states:

1st state: trickle charge: Vin =19V, Battery config is 4S Li ion Vcell <2V Ilimit= 2A Icharge max = 2A
2nd state: pre-charge: Vin =19V, Battery config is 4S Li ion Vcell <3V Ilimit= 2A Icharge max = 2A

3rd state: Normal CC charging (trickle & precharge is already done, termination charge not yet started) with I-limit=2A from 19V battery pack is 4S topology I charge = 2A enabled, Power path implemented. (the system does not take current from the input therefore max power can be directed towards the buck-charger)
What would interest me is the power dissipation of the IC (switching loss + conduction loss etc.).

4th state: Termination CV charge, Vin =19V, Battery config is 4S Li ion Vcell= 3.7V Ilimit= 2A Icharge max = 2A

Thank you for your help!

2

Hey Ervin,

There are no specific power calculation app notes at the moment, but we have evaluation boards that you can test with. Power loss can be related to the heat the IC generates, so if you get an evaluation board and observe how hot it gets, and note the thermal resistance [C/W], you should be able to get a rough estimate of how much power was loss.

Regards,
Jonathan Hidalgo

3

Thank you for the reply, I was hoping for a more mathematical solution, since development processes also need to address worst case estimates.