Other Parts Discussed in Thread: EV2400, CSD17551Q3A, CSD17308Q3, BQ24725A
Hello,
Taking my first steps with BQ25700A.
After running BQ25700A-EVM with EV2400, I printed a proto board.
I had a few CSD17308Q3 left from a previous buck only charger (BQ24725A) series, and after comparing CSD17551Q3A and CSD17308Q3 datasheets, I chose this last one for the proto.
Rds_on are similar, but Qg and Qgd are much lower with CSD17308Q3. So switching losses should be lower, right?
Did TI choose CSD17551Q3A for the BQ25700A EVM instead of CSD17308Q3 because it's newer? Apart from a lower Vgs for CSD17308Q3 (+10/-8V instead of +20/-20V), I don't understand why CSD17551Q3A should be more fit for this application.
Can someone tell me if I made a wrong choice, and if so, why?
If my choice is OK, where can I get some advice for placing vias under the thermal pad for heat conduction? Same guidelines as for CSD17551Q3A? No info for thermal vias on CSD17308Q3 datasheet.
Thank you.
Regards.
Matthieu.