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SunnySkyguy

  1. DIY LED Luminaires

    With power LED's mounted boards with adequate copper surface or aluminum surface area (~1 sq.in/Watt) cool emission of light can be adapted to almost any fixture with mindful avoidance of glare.

    I put these together one day for Winter Seasonal exterior lighting using surplus boards cut down to a 4S string and soldered with AWG 30 and soldered to a stringer of six (6) lamps using AWG 18 speaker wire with a length of 7 meters.

    I had a surplus 12V SMPS 2.5A brick and it ...
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  2. ON Semi Design Notes for LED drivers, SMPS , photo sensors and Triac Dimmers

    AND = Application Note Document (On Semi)
    DN = Design Note (On Semi) .pdf format


    These are all State of The ART LED's SMPS designs that may have started as University Grad Student/ Prof level designs, perfected by OnSemi and finally made their way into new chips with intelligent design, low cost, and high performance.

    Some are old 2010 and some are HOT off the press Design Notes.
    I have specially shared 25 APP Notes from ON, not directly listed
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  3. What's all this stuff about ISI and RLL? Anyhow?

    Coding Spacing is commonly generally defined by the range between data transitions to prevent DC content of data. Bi-Phase which is self -clocking but reliable and used in early Telephony 1.544Mb/s repeaters then tri-level coding was used. Similar starts in ethernet coding were used.

    Magnetic media , AC coding with the maximum bit density required the lowest transition rate in a binary transition coding method in early days was called MFM which put transitions on ones "1" ...
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  4. Spectrum Analyzer , SA Power measurement methods

    Power measurement methods for RF


    **Peak** = instantaneous maximum read with storage memory ( digital or Analog )often measured with Log Amplifiers calibrated in dBm for 50 or 75 Ohms


    **Average** = time interval averaged over specified interval


    Both above are computed by voltage detection into fixed resistance, calibrated to be ideal over spectrum bandwidth.


    **True RMS** = measured by temperature rise in a fixed resistance ...
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  5. AC-DC std LDO Capacitor calculation

    Design site has error in the design calculations for RMS >Peak.


    In the end the RMS voltage of the transformer should only be slightly more than the LDO Vdc if the optimal parts are selected.


    Assuming you want 5V,1A regulated choose LDO regulator with minimum drop otherwise 2.5V typical may require heat-sink , bigger cap. and bigger transformer.

    Assuming 50Hz with 100Hz rectifier ripple. produces narrow pulse current in caps (I_rms)
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