DO-213 Diode Package Temperature-Power Derating Curve [DO-213AA]
DO-213 Diode DC Wattage Derating Curve
How to derate a surface mount DO-213 package based on operating temperature.
Note the chart depicts maximum operating wattage vs End Cap temperature.
The curves are unrelated to any semiconductor, but only the package itself.
The DO-213 is a Surface Mount Device [SMD].
The package style is called a metal Electrode Leadless Face [Melf Definition].
MELF refers to the metal end-caps on either side of the package.
Derate Temperature by Device; Diode Derating Curves, by part number.
How to Derate; Guideline for Derating Components
Additional Styles of Diode Packages, with component details.
Editor Note: It's not that common to use a derating graph that only relates to a package. Normally a component is derated over temperature; that is, a semiconductor contained within a package that than forms a complete device. In almost all cases the component derating is concerned with insuring that the components junction temperature is kept below some maximum value, as the temperature is increased and or the current through the component is increased.
However it is possible to derate a part or component body, over temperature, that does not have a semiconductor junction that is sensitive to temperature. A connector having metal pins embedded within a plastic body is sensitive to over-heating by drawing to much current through the pins of the connector. So connectors are commonly derated on the basis of temperature and heat dissipation based on the current running through the pins.
So it is possible for a part or material to be sensitive to over-heating. Where at some point the material that makes up that package breaks down either due to the surrounding air temperature, the heat generated within the device as it conducts current or a combination of both ambient temperature and heat dissipation. The chart above shows those two conditions and is meant to be a design guide when using the DO-213 package.
Keep in mind that a component data sheet may provide a different graph. However, that graph would have to show numbers lower than the ones provided above. That is, if these number represent the maximum temperature the DO-213 can handle than once a semiconductor is placed within that device could not now exceed these number. And, in fact, might be lower because the junction temperature of the semiconductor might require a lower value.
A brief note on how to read the graph: the right most black line is the do not exceed line, and really a do not approach line. The lower black line is just included to indicate the normal slope or temperature any electrical data is collected at [if any]. In fact that line is in the same location for a great many dearting curves provided by this site. Operating at or under the two gray lines represent good design practice