DLPS147B January 2019 – May 2022 DLP4500NIR
PRODUCTION DATA
Micromirror array temperature cannot be measured directly, therefore it must be computed analytically using one or more of these conditions:
The relationship between the micromirror array and the case temperature is provided by the following equations:
PD × A × DMD Absorption Constant
where
PD = Illumination power density
A = Illumination area on DMD
An example calculation is provided in Equation 4 and Equation 5. DMD electrical power dissipation varies and depends on the voltage, data rates, and operating frequencies. The nominal electrical power dissipation is used in this calculation
with a power density of 2 W/cm2, an illumination area of 0.725 cm2, and a ceramic case temperature at TP1 of 55°C. The DMD absorption constant of 0.42 assumes nominal operation with an illumination distribution of 83.7% on the active array, 11.9% on the array border, and 4.4% on the window aperture. A system aperture may be required to limit power incident on the package aperture since this area absorbs much more efficiently than the array
. Using these values in the previous equations, the following values are computed:
+ QIllum = 0.442 W + (2 W/cm2 × 0.725 cm2 × 0.42) = 1.05 W
1.05 W
× 2°C/W) = 57.1°C