Having trouble with heat

[raburgeson]

Using lm307 as a summing amp for oxygen sensor trick. Works until chip burns up. Anyone know where I can order a few lm107 without having to take 500 of them. It's the same chip with a larger temperature operating range. It was made obsolete in 1995.

[spinner]

Using lm307 as a summing amp for oxygen sensor trick. Works until chip burns up. Anyone know where I can order a few lm107 without having to take 500 of them. It's the same chip with a larger temperature operating range. It was made obsolete in 1995.

An Op-amp working as a summing amp should not overheat under normal operation/conditions. Can you provide some details of your circuit/application?
Is it the surrounding heat which makes your chips "melting"?

National 1XX series was always quite expensive.. (some series have "Military" & "Life Support equipment" certificates...)

I'm sure you can find a suitable (modern) replacement...
Cheers!

[raburgeson]

Yes it's surrounding heat, it's like a quarter watt signal and moving it to the outside of the radiator support causes to much drop from length resistance. Trying to make a much cheaper way to trick the O2 sensor. The computers has an anolog/digital converter that only requires nano amperes but the voltage must be very precise.

307 series was doing a good job as long as they last. I can only speak for Chevy on this. I haven't added the water4gas system yet. I could lean the engine until it pinged in all speed ranges though. So, I was leaning it.