Hello,
I am turning to you all for help with BQ24650 charger design that has proven to be difficult lately and was unable to debug it with significant effort.
The problem is very simple, using this charger even with low currents of about 500mA the IC itself overheats and falls into thermal shutdown. Since there should not be any power conversion path via the IC itself, this should not be happening without charging.
We have made two revisions of the PCB to exclude any manufacturing induced errors as well as assembly/soldering bugs with several prototypes.
All the operating parameters as defined in the datasheet and reference design BQ24650EVM are as specified and the regulated output voltage is stable. Power consumption of the charging circuit in standby is 10mA, no battery connected.
Design is published at: https://github.com/IRNAS/ServalRuggedBatteryPack/tree/master/electronics/V3 Note that in testing the rest of the design has not been populated, just the Charging section tested.
I am happy to provide any other information if required, currently I do not have the prototype at hand to perform additional measurements but can do that shortly. Any other thoughts on the design are welcome.