2
\$\begingroup\$

I recieved samples of AD7175-2 and AD5684R with an instruction:

If these samples are to be subjected to solder reflow or high temperature process, they must be baked for 24 hours at 125°C prior board mount. Failure to comply may result in crack and/or delamination of critical surfaces within the package.

Is it done in a reflow oven? Otherwise how?

I am confused because Elektor qs-5188C reflow oven in our lab seems to lack an option, that would let it run for such a long time.

\$\endgroup\$
  • 1
    \$\begingroup\$ You put it in whatever place for 24 hours that you can keep at that temperature. For a production reflow system it would be stupid to do it within the reflow oven since it is blocked for that time for more useful work. But for a one-off prototype it might be ok, given the other parts are fine with that too \$\endgroup\$ – PlasmaHH Jul 20 '17 at 14:26
  • \$\begingroup\$ 125 degrees can be maintained in a conventional oven if you're just prototyping. \$\endgroup\$ – horta Jul 20 '17 at 14:28
  • \$\begingroup\$ @horta You mean an oven in a kitchen would do it? but it lacks proper temperatire regulation \$\endgroup\$ – Andrey Pro Jul 20 '17 at 14:31
  • \$\begingroup\$ @AndreyPro You can use a kitchen oven for this, you would just need to ensure that the temperature stays consistent by measuring the temperature inside the oven. \$\endgroup\$ – Joe S Jul 20 '17 at 14:33
  • \$\begingroup\$ @AndreyPro: Then your oven is crap, mine can keep temperature within 5°K just fine. \$\endgroup\$ – PlasmaHH Jul 20 '17 at 14:37
2
\$\begingroup\$

The whole point of performing this pre-bake before soldering or reflowing the devices is to ensure you've slowly pushed out any h2o. If you don't do this, if you go straight to soldering or reflow, the sudden high temperatures can cause the h2o to go straight to steam in a hurry causing catastrophic separation of parts within the device.

You can bake these parts at 125 degrees in any oven that will maintain that temperature (conventional, reflow, convection). It doesn't have to be terribly accurate so long as you can gently/slowly evaporate the h2o. After this is done, any shock temperature isn't going to cause issues during the soldering/reflow process.

\$\endgroup\$
2
\$\begingroup\$

So long as the temperature and the time are correct, you can do this with any oven. (including a reflow oven). As stated in the comments, in a production environment it is not advisable to use a reflow oven for this because it ties up the oven for an extended period of time where it cannot be used for reflow, but for a prototype environment the end result will be the same.

\$\endgroup\$
  • \$\begingroup\$ Or I could save the trouble and solder these 2 chips by hand. Do you think it would be alright? \$\endgroup\$ – Andrey Pro Jul 20 '17 at 14:52
  • \$\begingroup\$ @AndreyPro Soldering elements by hand is a high temperature process and has the chance to break your components. \$\endgroup\$ – horta Jul 20 '17 at 14:54
  • \$\begingroup\$ As said in your post: "Failure to comply may result in crack and/or delamination of critical surfaces within the package." \$\endgroup\$ – Joe S Jul 20 '17 at 14:55
  • \$\begingroup\$ Hand soldering doesn't usually heat the parts enough to make them come unstuck. If you work at normal speed, things don't have time to really heat up. \$\endgroup\$ – JRE Jul 20 '17 at 18:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.