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DLPC900: Pattern-on-the-fly mode configuration

Part Number: DLPC900

Hi E2E,

Good day.

Our customer is using a light engine with DLPC900 chipset. They would like to use either pattern-on-the-fly mode or pre-stored pattern mode to run 10,000+ patterns. However, they cannot load more than 50 patterns with 8-bit depth to the onboard storage using pattern-on-the-fly mode. Is there any method to run pattern-on-the-fly without loading them to onboard memory so that they can run 10,000+ patterns?

Regards,
Carlo

  • Carlo,

    This is a limitation of the DDR memory on board the DLPC900.  It can store 400 1-bit patterns.  If you run 8-bit patterns then 400/8 = 50 patterns.

    A different way to approach this is to use Video Pattern Mode and pack the images into video frames.  There can be up to three 8-bit patterns embedded into a video frame.  What they would do is embed the patterns into a video stream and then show them over Video Pattern Mode.

    Maybe a little bit more detail on what they want to accomplish will help. Like, how long do they need to display each pattern? What 8-bit pattern rate do they want to reach?  . . .  

    FIzix

  • Hi Flzix,

    Thank you for your response. With our customer light engine, they are using the DMD to independently pattern two different light sources. This is done by first turning on one LED and patterning the DMD. Then, the first LED is turned off and the second LED is turned on and the DMD is switched to a different pattern. They want the pattern to appear concurrent, so the process of LEDs on/off and changing the DMD pattern needs to happen as fast as possible. They need to use 8-bit depth, so the fastest pattern that can be alternated is at 4046 us.

    They are also using this light engine for 3D printing, which normally requires thousands of patterns to be loaded without independent patterning. With the independent patterning, it will probably need upwards of 50,000-100,000 patterns. However, their light engine only works using pattern-on-the-fly or pre-store modes. Is there any way to upgrade the storage of the chip or have it pull directly from a desktop PC storage?

    Regards,
    Carlo

  • Hello Carlo,

    I think there is some confusion here.  What is meant by, "They want the pattern to appear concurrent"?  Do they mean within the same video frame?  The 8-bit patterns would have to be sequential.

    Regarding the second question, with this chip, there is not a way to connect the memory of the PC directly to the controller in the way they are suggesting.  That is what video pattern mode is for.  It is a way for the PC to read memory and pack it into an HDMI/DP stream.  It is also possible to connect directly to the RGB input and send an RGB stream, but it will still be "Video Pattern Mode" and would require a board in the PC to pack the data into a parallel RGB stream.

    Fizix