DLPS269A March   2025  – June 2025 DLP991UUV

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  Storage Conditions
    3. 5.3  ESD Ratings
    4. 5.4  Recommended Operating Conditions
    5. 5.5  Thermal Information
    6. 5.6  Electrical Characteristics
    7. 5.7  Switching Characteristics
    8. 5.8  Timing Requirements
    9. 5.9  System Mounting Interface Loads
    10. 5.10 Micromirror Array Physical Characteristics
    11. 5.11 Micromirror Array Optical Characteristics
    12. 5.12 Window Characteristics
    13. 5.13 Chipset Component Usage Specification
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Power Interface
      2. 6.3.2 Timing
    4. 6.4 Device Functional Modes
    5. 6.5 Optical Interface and System Image Quality Considerations
      1. 6.5.1 Numerical Aperture and Stray Light Control
      2. 6.5.2 Pupil Match
      3. 6.5.3 Illumination Overfill
    6. 6.6 DMD Temperature Calculation
      1. 6.6.1 Off-State Thermal Differential (TDELTA_MIN)
      2. 6.6.2 On-State Thermal Differential (TDELTA_MAX)
    7. 6.7 Micromirror Power Density Calculation
    8. 6.8 Micromirror Landed-On/Landed-Off Duty Cycle
      1. 6.8.1 Definition of Micromirror Landed-On/Landed-Off Duty Cycle
      2. 6.8.2 Landed Duty Cycle and Useful Life of the DMD
      3. 6.8.3 Estimating the Long-Term Average Landed Duty Cycle of a Product or Application
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
    3. 7.3 DMD Die Temperature Sensing
  9. 8 Power Supply Recommendations
    1. 8.1 DMD Power Supply Power-Up Procedure
    2. 8.2 DMD Power Supply Power-Down Procedure
  10. 9 Layout
    1. 9.1 Layout Guidelines
      1. 9.1.1 PCB Design Standards
      2. 9.1.2 General PCB Routing
        1. 9.1.2.1 Trace Impedance and Routing Priority
        2. 9.1.2.2 Example PCB Layer Stack-Up
        3. 9.1.2.3 Trace Width, Spacing
        4. 9.1.2.4 Power and Ground Planes
        5. 9.1.2.5 Trace Length Matching
          1. 9.1.2.5.1 HSSI Input Bus Skew
          2. 9.1.2.5.2 Other Timing Critical Signals
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Device Nomenclature
      2. 10.1.2 Device Markings
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Package Option Addendum

6.6 DMD Temperature Calculation

DLP991UUV DMD Thermal Test PointsFigure 6-1 DMD Thermal Test Points

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

TMAX_ARRAY = TCERAMIC + (QARRAY × RMAX_ARRAY-TO-CERAMIC)
TMIN_ARRAY = TCERAMIC + (QARRAY × RMIN_ARRAY-TO-CERAMIC)
TDELTA_MIN = [minimum of TP2 or TP3] – TMAX_ARRAY
TDELTA_MAX = [maximum of TP2 or TP3] – TMIN_ARRAY
QARRAY = QELECTRICAL + QILLUMINATION

where

  • TARRAY = Computed array temperature (°C)
  • TCERAMIC = Measured ceramic temperature (°C) (TP1 location)
  • RARRAY-TO-CERAMIC = Thermal resistance of package from array to ceramic TP1 (°C/Watt)
  • QARRAY = Total DMD power on the array (Watts) (electrical + absorbed)
  • QELECTRICAL = Nominal electrical power
  • QINCIDENT = Total incident optical power to DMD
  • QILLUMINATION = (DMD average thermal absorptivity × QINCIDENT) (See Section 5.4.)
  • DMD average thermal absorptivity on-state = 0.26
  • DMD average thermal absorptivity off-state = 0.42

The electrical power dissipation of the DMD is variable and depends on the voltages, data rates, and operating frequencies. To calculate array temperature, the value for electrical power dissipation of the DMD (QELECTRICAL) is 9.5 Watts. The absorbed power from the illumination source is variable and depends on the operating state of the micromirrors and the intensity of the light source. The equations shown above are valid for each DMD chip in a system. It assumes an illumination distribution of 91.0% on the active array and 9.0% on the array border.

Sample calculations for off-state and on-state are shown below.