bq40z60 not switched around 1MHz during charging

Hi all

I want to use BQ40z60 for charging and gauging of the 4-cell 2200 mAH batteries.

I designed my custom hardware with BQ40z60. However I made the board based on BQ40z60 comments and hints, some problems I have been faced with:

1- the input ACFET never turns ON, and the current flows through the body diode of the transistor, (The ACFET pin voltage is just the AC input voltage).

2- The gate frequency of the high side switch of the buck charger is not around 1MHz, it is around 40kHz, with most of the time ON. Moreover the gate signal does not seem to be a clean signal.

3- The gate of the low side switch of the charger never rises and the just its body diode does the switching.

any comments would be appreciated.

sadi