Maximum junction temperature for L78

[Yoshi_]

Hello.

I would like to know the maximum Tj value of L78.

I think the junction temperature of silicon semiconductors is generally 150°C, but the data sheet states that the operating junction temperature range is 0 to 125°C for L78 and 0 to 150°C for L79.

The solid line in Figure 31 of the data sheet seems to go up to 150°C,
but is the starting point for thermal design 125°C?

Thank you in advance.

[Peter BENSCH · Accepted solution]

Welcome @Yoshi_, to the community!

The maximum junction temperature is actually 125°C, as stated in the data sheet of the L78. The 150°C found there is only the maximum storage temperature.

Figure 31 only shows the typical performance and the switching off of the output voltage at the upper limit. However, the absolute maximum ratings in table 1 are decisive for the design.

Does that answer your question?

Regards
/Peter