Tonight after I finished replacing the headers on a MPU 100 I decided to bench test the new work. Using my oscilloscope I was testing for activity on the new headers. The board was in attract mode (seven flashes). When I laid my arm on the board I noticed U7 and U8 felt quite warm. (About 90 degrees). After I finished my tests I checked the temperature. I needed something to compare so I turned on my Meteor. The ROMs were all about the same - 90 degrees. However, U7, U8, U9, U10, and U11 were all about 8 to 10 degrees warmer on the MPU 100 on the bench.
Is this normal?
Should I be concerned?
What is the normal operating temperature of these IC’s?