User:Chotee/NoFeedback-ManagementIntervention

1mx1m screen of RGB lights that slowly and independently change colour. All patterns are just your mind playing tricks on you.

Parts

• [Ordered] LEDs - https://nl.aliexpress.com/item/free-shipping-500pcs-5mm-Straw-Hat-Colorful-Slow-Flashing-Flash-RGB-Red-Blue-Green-LED-Leds/32231092414.html
• 11 x duct (11*€3) https://www.gamma.nl/assortiment/snoergoot-wit-9x5mm-wit-2-meter/p/B651984
• 10 Bouten M6x80mm €8 - https://www.gamma.nl/assortiment/gamma-slotbout-m6x80-mm-verzinkt-20-stuks/p/B458213
• 1000x1000mm Plexiglas - €23 - https://www.gamma.nl/assortiment/martens-acrylplaat-transparant-100x100-cm/p/B151681

Electronics

• 500 Slow color changing RGB leds.
  • max led forward current is 20mA.
  • RGBs forward-voltage oscillates between 3.2v and 3.8v (±15%)
  • LEDs max continious current at 20mA.
• 22x22 leds (484) [sqrt(500) = 22.36..]
• Powered by 12v PC PSU or 20v LT power-brick.

12v

• 12v/3.8 (V-max-led-forward) = 3.15 LEDs; 3 LEDs in a chain.
• There are 161+1/3 chains [484/3]
• Vmax = 3 * 3.8Vf = 11.4v; 0.6v left.
• Vmin = 3 * 3.2Vf = 9.6v; 2.4v left.
• current limit power-max: 2.4v*20mA = 48mW.
• Total Current: 20mA * 162 = 3.24A
• Total power: 3.24A * 12v = 38.8w

20v

• 20v/3.8 (V-max-led-forward) = 5.2 LEDs; 5 LEDs in a chain.
• There are 96.8 chains [484/5]
• Vmax = 5 * 3.8Vf = 19v; 1v left.
• Vmin = 5 * 3.2Vf = 16v; 4v left.
• current limit power-max: 4v*20mA = 80mW.
• Total Current: 20mA * 97 = 1.94A
• Total power: 1.94A * 20v = 38.8w

Components

• R1 = 100k
• R2 = 1k8
• Rs = 10
• Opamp >20v
• Mosfet. >20v; >20mA

== Circuit: [from http://www.falstad.com/circuit/circuitjs.html]

$ 1 0.000005 10.20027730826997 50 5 50 w 544 512 416 512 0 w 416 496 416 512 0 v 416 496 416 224 0 0 40 12 0 0 0.5 g 416 512 416 544 0 w 416 224 544 224 0 w 544 224 544 256 0 f 688 384 752 384 0 1.5 0.02 162 752 224 752 272 1 3.2 1 0 0 0.01 162 752 272 752 320 1 3.2 1 0 0 0.01 162 752 320 752 368 1 3.2 1 0 0 0.01 r 752 448 752 512 0 10 w 544 224 752 224 0 w 544 512 608 512 0 w 608 512 752 512 0 w 544 480 544 512 0 w 752 400 752 448 0 w 752 448 608 448 0 w 608 400 608 448 0 w 544 368 608 368 0 a 608 384 688 384 1 15 -15 1000000 0.2121490597382403 0.21218074656188607 r 544 272 544 368 0 100000 w 544 272 544 256 0 r 544 368 544 480 0 1800