16F876A chip failures

[badrad]

Well, I have same problems like you have Badrad , I am totally agree with Mister e but my case all unused pins set it up input and tide up the ground, however among 200 PCS PIC 16F876A 20/P 40PCS was still totally broken After some time,

And strange thinks that some of them look like works but some ports are defected.


Finally we trace the problem from EMI interferences chip affected, at the moment it looks okay, but still worry? May be also it is good idea to look some other problems.
Also for your information I changed controller from previous one to PIC 16F876A I/SP

regards

So, I am not totally alone with my problems...
Did you rework your design or shield your PIC?

As for my problem, since then, I had to rework my pcb and included the following:
1. left the unused pins alone, but defined them as outputs. (now this might sound contrary and I did initially ground them and assign as inputs, but the tech people at Microchip recommended this to me).
2. put in sufficient ground plane.
3. installed MOV at my A/D input as well as at the power input.
4. increased my A/D input resistor from 1K to 20K.
5. keep my fingers crossed...

All my PICs have been the 16F876A I/SP.