BQ77905: Upper BQ77905 CTRC/CTRD contected to VSS in 13S

Part Number:BQ77905

Dear Colleague,

In the case of multi-chip cascade, chip 2 transmits protection action by receiving CHGU/DSG signal of chip 1. Under normal circumstances, the high-level output of CHGU and DSG pins of chip 1 can be detected by the CTRX of chip 2, so chip 2 can be judged that chip 1 has no protective action. However, the CTRD and CTRC of the chip 1 are connected to the ground, which is the same as the signal that the chip 2 receives when the chip 1 is protected (CHGU/DSG is low). In both cases, the inputs are the same, but the output is different.

So how to explain this logic?

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Thanks a lot!

B.R

Rock Su