DLPU066A March   2018  – April 2022

 

  1. 1Calibration Purpose
    1. 1.1 Calibration Purpose
    2. 1.2 Goal of Calibration
  2. 2Calibration Software and Tools
    1. 2.1 Calibration Software and Tools
  3. 3Calibration Setup
    1. 3.1 Calibration Setup
  4. 4Calibration Overview and Theory
    1. 4.1 Goal of Calibration
    2. 4.2 Calibration Background
      1. 4.2.1 Calibration File Parameters
      2. 4.2.2 Coarse Adjustment Parameter Combinations
    3. 4.3 Calibration Process
      1. 4.3.1 Calibration Pre-work: Coarse Combination Determination
      2. 4.3.2 Temperature Charaterization
      3. 4.3.3 Production PGU Calibration
  5. 5Calibration Pre-work
    1. 5.1 Pre-work Overview
    2. 5.2 Coarse Combination Determination
    3. 5.3 Strategically Adjusting Coarse Combination Parameters
      1. 5.3.1 LDC Index
      2. 5.3.2 Optical Sensor Feedback Gain
      3. 5.3.3 Current Limit
    4. 5.4 Coarse Combination Strategies
  6. 6Calibration Procedure
    1. 6.1 Calibration Procedure Overview
    2. 6.2 Calibration Sweep Setup and Coarse Combinations
    3. 6.3 Temperature Characterization
    4. 6.4 Production PGU Calibration
    5. 6.5 Generating a Calibration File
  7. 7Revision History

4.3.3 Production PGU Calibration

During production, each PGU needs to be calibrated to determine fine adjustment parameters to ensure smooth dimming and color point accuracy across all coarse combinations. This LED PWM sweep must be performed at one of the temperatures used in the temperature characterization portion (usually room temperature). Only one temperature calibration table needs to be measured, as the rest can be mathematically calculated from the pre-production calibration data. These calibration tables, calculated across the operating temperature range, are combined into the final calibration file and stored on each individual PGU, ensuring individual dimming and white point accuracy.

See Section 6.4 for more details on the production PGU calibration procedure.