Hello sir.
The DP83640 is on module board inside the switchboard.
At present, when encountering the Siemens 7SJ82 model terminal, there will be a problem of compatibility with the Pin lost.
Replacing the terminal or module board without DP83640 will not cause problems. Only when the DP83640 is connected to the Siemens 7SJ82 model terminal will there be compatibility problems.
We used freeze spray or heat gun for 2 to 3 seconds to find out that the situation is more serious. This is all in the working range of the IC.
Do you have any suggestions to solve this problem? Thanks for kindly help~