AN1149-4 Lumileds Lighting, LLC, AN1149-4 Datasheet - Page 13

• Manufacturer Part Number: AN1149-4
• Description: Thermal Management Considerations for SuperFlux LEDs
• Manufacturer: Lumileds Lighting, LLC

Step 8: Measure the V
heating current (V
Step 9: Turn off all power to the lamp, and
immediately (≤ 10 ms) re measure the V
the DUT at the test current selected in 6).
Step 10: Calculate the ∆T
dividing the ∆ V
the appropriate factor in Table 4.3.
Table 4.3
f
(∆V
f
heating).
f
in junction temperature for high-brightness led materials
= V
Ratios of the change in forward voltage vs. the change
f
of the DUT at the
f
LED Material Type
(Step 6)
j
of the DUT by
AS AlInGap
TS AlInGap
V
f
(Step 9)
f
of
) by
13
Step 11: Calculate the power, P, into the DUT by
multiplying the heating/design current by its
corresponding V
Step 12: Calculate R
P calculated in Steps 10 and 11. Lumileds can
provide the R
assemblies as described above as a service to its
LED customers.
∆ V
f
/
∆ T
-2.0
-2.0
j
θ
ja
( mV / °C)
measurements of LED lamp
f
heating as determined in Step 8.
θ
ja
using the values of ∆T
j
and