Hi. We are considering the MP2667 but we are concerned about how hot it will get. Target charge current is 800mA and, with a flat cell (say, 3.5V), this is 1.2W. Are there any tricks we can use to reduce the thermal resistance? Would wider tracks to IN, SYS, BATT and GND pins or a copper area under the chip help? Thanks.
Hi lesgrant,
If we optimize the layout of the board, the MP2667 should perform well despite higher charge currents. The best example of an optimized layout is the evaluation board of this device. If you stick to that design as closely as possible, I believe you should have good thermal performance. If you are interested in design files for the evaluation board of the MP2667, I should be able to email you Altium files if you can use them. Please email us at mpsnow@monolithicpower.com requesting those files. You can regerence this interaction as well.
Thanks,
Brendan Schoemehl
Field Applications Engineer
Monolithic Power Systems | MPS Now
Hi Brendan. Thanks for the quick response. I will email a request for the Altium files - thanks. I have also realised that I can dynamically control the power dissipation by controlling the charge current as the application already measures the incoming supply voltage and the battery voltage. Thanks again. 
Hi lesgrant,
I reached out to you via email. Please be on the look out for that.
Brendan