JAJSGI1 November   2018

PRODUCTION DATA.

1. 特長
2. アプリケーション
3. 概要
1.     Device Images
4. 改訂履歴
5. Pin Configuration and Functions
6. Specifications
7. Software Requirements
8. Detailed Description
9. Application and Implementation
1. 9.1 Application Information
2. 9.2 Typical Application
10. 10Power Supply Recommendations
11. 11Layout
12. 12デバイスおよびドキュメントのサポート
1. 12.1 デバイス・サポート
2. 12.2 関連リンク
3. 12.3 コミュニティ・リソース
4. 12.4 商標
5. 12.5 静電気放電に関する注意事項
6. 12.6 Glossary
13. 13メカニカル、パッケージ、および注文情報

• FQL|100

### 8.6 Micromirror Array Temperature Calculation Figure 18. DMD Thermal Test Points

Micromirror array temperature can be computed analytically from measurement points on the outside of the package, the ceramic package thermal resistance, the electrical power dissipation, and the illumination heat load. The relationship between micromirror array temperature and the reference ceramic temperature is provided by the following equations:

Equation 1. TARRAY = TCERAMIC + (QARRAY × RARRAY–TO–CERAMIC)
Equation 2. QARRAY = QELECTRICAL + QILLUMINATION
Equation 3. QILLUMINATION = (CL2W × SL)

where

• TARRAY = Computed DMD array temperature (°C)
• TCERAMIC = Measured ceramic temperature (°C), TP1 location in Figure 18
• RARRAY–TO–CERAMIC = DMD package thermal resistance from array to outside ceramic (°C/W) specified in Thermal Information
• QARRAY = Total DMD power; electrical plus absorbed (calculated) (W)
• QELECTRICAL = Nominal DMD electrical power dissipation (W)
• CL2W = Conversion constant for screen lumens to absorbed optical power on the DMD (W/lm) specified below
• SL = Measured ANSI screen lumens (lm)

Electrical power dissipation of the DMD is variable and depends on the voltages, data rates and operating frequencies. A nominal electrical power dissipation to use when calculating array temperature is 0.25W. Absorbed optical power from the illumination source is variable and depends on the operating state of the micromirrors and the intensity of the light source. Equations shown above are valid for a 1-chip DMD system with total projection efficiency through the projection lens from DMD to the screen of 87%.

The conversion constant CL2W is based on the DMD micromirror array characteristics. It assumes a spectral efficiency of 300 lm/W for the projected light and illumination distribution of 83.7% on the DMD active array, and 16.3% on the DMD array border and window aperture. The conversion constant is calculated to be 0.00266 W/lm.

Sample Calculation for typical projection application:

1. TCERAMIC = 55°C, assumed system measurement; see Recommended Operating Conditions for specification limits.
2. SL = 1500 lm
3. QELECTRICAL = 0.25 W
4. CL2W = 0.00266 W/lm
5. QARRAY = 0.25 + (0.00266 × 1500) = 4.24 W
6. TARRAY = 55°C + (4.24 W × 1.1°C/W) = 59.66°C