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Maximize LED output using only one LED

Hi

I have a DLP LightCrafter Evaluation Module (EVM) and I only need output from one of the LEDs. (I am doing Phase Shifting Profilometry.)

I don't have active cooling so I set e.g. the red LED current value to 274 giving an LED current of 633mA. This is however not enough output for my application.

When I never uses more then one LED at a time, can I then using only passive cooling set the output of e.g. the green and blue LED to zero and e.g. the red LED current value to 274*3=822 giving an LED current of 1899mA?

I is important to note that I only flash the LED for a very short time and then have a short pause before showing the next pattern.

The different scenarios are as followes:

  1. Light on for 18ms, pause 784ms, repeat 12 times, stop for at least six seconds and in most situations several minutes.
  2. Light on for 18ms, pause 460ms, repeat 30 times, stop for at least six seconds and in most situations several minutes.
  3. Light on for 150ms, next pattern, light on for 150ms, repeat 12 or 30 times, stop for at least six seconds and in most situations several minutes.

How do I get more light output in the above described situation?

Thansk.

Best Regards

Kristian

  • Hi Kristian,

    Should be fine I think. You can crank-up to current settings upto 1024. Additionally on the EVM there is MSP430 microcontroller which is running the Temperature sensing, Over voltage sensing, and LED enable signal stuck high, protection functions, so MSP430 shutdown the system if any such event occurs.

    Regards,

    Sanjeev

  • Hi Sanjeev

    Thank you very much for your answer.

    Just to clarify that I read you response correctly. Do you mean I can set the LED current value to 1024 giving an LED current of approximately 2A? *

    Given that:
    1) I only do this for one of the LEDs.
    2) I set the other two LEDs current value to zero.
    3) I only flash the LED as described above.

    (*Computed as LED Current (mA) = 1.8 × (LED Current Value) + 140, as described in section 2.4 in the manual.)

    Regards Kristian