Yes, you probably did :-(

Many (most) modern ic's have diode protection so that if a pin is raised to
a voltage above Vcc, current is conducted to Vcc, and if voltage is dropped
below ground, current is conducted to ground. Unfortunately, when you swap
ground and Vcc, these diodes go into conduction and conduct a large current,
usually getting damaged in the process.

Whether or not protection diodes were involved, the fact that the chip got
hot is a good indication that you can replace it..

Cheers
 Roland

----- Original Message -----
From: Steven Rightnar <rightnar@DOMINION.LLUMC.EDU>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, March 07, 2000 9:11 PM
Subject: analog to digital problem


> Hi all:
>     I am using a TI TLC548IP ADC and it outputs  go into a 16F84. I
plugged
> the thing in backwards and it got HOT. My question is how robust are
analog
> to digital converters. Looking at it now I had the +5 and the ground
> swapped. Now the circuit worked on the breadboard so I made a PCB put all
> the components in checked everything twice. Fired it up and nothing so I
> checked everything and got burnt by the ADC. I could not find anything
else
> wrong. So did I fry the ADC?
>
> Thanks for any help,
>
> Steven
>