DLPU066A March   2018  – April 2022 DLP3030-Q1

 

  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

5.3.3 Current Limit

In continuous mode operation, current limit serves as a protection mechanism by setting the maximum current allowed through the LEDs. Since continuous mode is used for high brightness outputs, current limits should be set to the maximum value of 59,000 (corresponding to 6 A for the green and blue LEDs, 4.5 A for the red LED) for all continuous mode coarse combinations. Note: continuous and discontinuous modes are set by choosing LDC index. the configuration file overview has a list of which LDC indexes are continuous mode and which ones are discontinuous mode.

In discontinuous mode, current limit sets the current through the shunt FET, which is then used to create discontinuous mode pulses. Discontinuous mode current limit should be reduced to limit current overshoot through the LEDs. DM current limits should, at maximum, be set to 30,000.

Decreasing the current limit of a discontinuous mode coarse combination will decrease the minimum achievable brightness output. In some cases this may also increase the achievable brightness range of the coarse combination.