Thin film resistors are usually far more expensive than thick film resistors. For example, SMD thin film resistors, with 0.5% tolerances, and with 25 ppm/K temperature coefficients, when bought in full size reel quantities, are about twice the cost of 1%, 250 ppm/K thick film resistors. Source: Wikipedia
2. The majority of the time adding a resistor to the data line is completely pointless. It only has an effect if the Arduino and the first WS2812B chip are connected over a long cable. By "long" I'm talking meters, not centimeters. The length of the strip of LEDs is irrelevant as each LED generates a fresh signal to send to the next LED.
Start by applying flux on all the pads on the circuit board. Apply some solder to one of the chip’s corner pads. Place and align the chip using tweezers. Hold the chip in place while touching the corner pad with the tip of the soldering iron so that the solder melts the pin and the pad together. Check the alignment of the chip.
Sorted by: 4. 20 red leds (so 2.0 Vf at 20 mA) in series is 20 * 2.0 = 40 volts at 20 miliamps. That's 40 * 0.02 = 0.8 Watts. 20 red leds in parallel is 20 * 0.02 = 0.4 Amps or 400 mA at 2 Volts. That's 2 * 0.4 = 0.8 Watts. There is no difference in power used, just how you wire it. Current is shared in Series circuits, Voltage is shared in
I thought the only reason for fitting resistors to led's was so that when you are indicating they will register on the dash to let you know your indicators are working . I tow some trailers at work with led's and no resistors and they are a pain as you don't know from the cab if your indicators are actually working , don't think you will do the
