OVTL09LG3A Datasheet, PDF (9/11 Pages) OPTEK Technologies – 10-Watt Lednium SMD (120° Viewing Angle)

10-Watt Lednium SMD
OVTL09LG3x Series
Typical elements in the conducting path and corresponding nominal thermal conductivities are:
Epilayers
Substrate
Die attach material
Package
Solder
Copper cladding
Elements
GaN/InGaN
Sapphire
Conductive epoxy
Silver plated copper
Solder (Sn/Ag/Cu)
Copper
w/mK
150
50
10
350
35
300
Note : Thermal conductivity is a physical constant. For the materials above, the respective contribution each makes
to the overall thermal resistance (Rθ _j-b) is a function of the thickness of each material layer, and the surface area.
Thermal Conductivity (TC) is defined to be the heat conducted in time (t), through thickness (T) in a direction normal
to a surface area (A), due to a temperature difference (δT).
Therefore
TC= q/t x {T/[A x δT]}
and
δT = [Q x T]/[A x TC] where δT = Temp. difference (K)
Q = Power (w)
A = Surface area (m²)
T = layer thickness (m)
TC = Thermal Conductivity (w/mK)
Theoretical Calculation (for 1 watt dissipated in a cup product via a single 40mil die)
GaN
Thickness approx 10 x 10^-6
Area 10^-6
= 1 x 10x10^-6/ 10^-6 x 150
= 0.07 K
Substrate
T = 60 x 10^-6
= 1 x 60x10^-6/ 10^-6 x 50
= 1.2 K
Die attach
T = 20 x 10^-6
A = 2 x 10^-6
= 1 x 20x10^-6 / 2x10^-6 x 10
=1
Package
T = 0.4x10^-3
A = 6x10^-6
= 1 x 0.4x10^-3/ 6x10^-6 x 350
= 0.19
Solder
T = 60x10^-6
A = 6x10^-6
= 1 x 60x10^-6/6x10^-6 x 25
= 0.4
Total Calculated δT = 2.86K
OPTEK reserves the right to make changes at any time in order to improve design and to supply the best product possible.
OPTEK Technology Inc. — 1645 Wallace Drive, Carrollton, Texas 75006
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