driving the data bus without powering the 68013,does this damage the chip?

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Anonymous
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Driving the data bus or control pins without powering the 68013,does this damage the chip?

   

I have destroyed two chips these days. 

   

The short life time of 68013 reminds me that there must be something wrong in the operation.

   

I think it  would be a cause that drive the data bus without powering the 68013. Is it right? 

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Bob_Marlowe
Level 10
Level 10
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In my datasheet are under "Absolute Max. Ratings" two items that might apply.

   

first: DC voltage applied to oputputs in Hig-Z : -0.5V to Vcc +0.5V. In your case Vcc is 0V

   

second: DC voltage to any input pin with a note #15 saying DO NOT POWER I/O WHITH CHIP POWER OFF

   

 

   

So you are on rough, not on fairway.

   

 

   

Bob

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Anonymous
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Yes. You should not power I/Os with out powering the chip.

   

Regards,

   

sai krishna.

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Anonymous
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Thank you all.

   

Regards,

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Anonymous
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Trying to get some more detail on what "Do not power the I/O without powering the 68013" actually means.

   

 

   

We are using the 68013a as a usb to parallel port adapter for a specific legacy product.  I am in the process of cleaning up the design, and there is a transistor setup to pull up the Data lines after the chip comes up.  What about when the chip is connected (As a product) to a parallel port, would this also be a problem, and if so, how would one over come the issue?

   

 

   

Trying to understand why the I/O lines can't be powered (other than the obvious) or what kind of powering can they take .

   

 

   

Thanks

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