L9963E BMS front-end: SPI + isolated daisy-chain?

[FRosc.1]

Hello,

I am looking for an AFE for a BMS for a vehicle battery. An option would be part L9963E.

The battery is 28 cells in series, hence two 14-channel AFEs would be necessary.

The BMS is centralized, on one PCB. I would like to keep the communication simple and am considering the following topology:

The microcontroller shares ground with battery V-, so I would like to connect to the AFE using SPI. The second AFE is at ~60V higher potential, so I'd like to use the isolated daisy-chain interface between the AFEs for that.

Is this topology possible? I checked the datasheet but it does not mention this topology, it only mentions one with the bottom AFE using isolated interface via a converter IC (which I would like to avoid if possible).

[Elena BRAMBILLA]

hello

functionality is ok, but isolation requirements may be violated. The system works, but the safety could be not granted in case of faults: up to system maker to define a fault handling strategy. regards.

Elena