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If only one LED lamp is connected, how much current limiting resistance is required for 12V DC power supply?
Is there a manual for LED lamp? If there is, it will give the working current of LED lamp. If you divide the working current by 12-0.7, that is the resistance. If there is no manual for LED lamp, according to my experience, you should design according to 5mA, that is, 12-07 / 5mA = 2.3k Ω, here 0.7V is two poles
12V connected to 56 LEDs need to connect how much resistance or what buck circuit, the best circuit diagram
I now have 10 white LED tubes, one 3.2v-3.4v, connected with a 39 ohm resistor, and the voltage is about 3.1V. Is it OK to connect 12V directly without resistance?
LED is not a pure resistance device. LED is about voltage drop. Generally speaking, the voltage drop of LED in the market is 1.2V, and the resistance value is between 150 and 700 Ω
The voltage drop of 8 LEDs in series is 12 ~ 16V, so I suggest
56 are divided into seven groups, eight in each group, eight in series, and then seven groups in parallel
Or 7 in series for each group and 8 in parallel for each group
Six LED lights in series, connected to 12V power supply, how to string resistance? How big is the string?
Six Φ 8 Blue LED lights are connected in series with 12V power supply. How to connect the resistance? How big is the connection?
I remember the blue LED is 2.7V
The six can be divided into two groups, three in series into a group, the working voltage is about 8.1v, the remaining voltage is 3.9v as the working voltage of the current limiting resistor
Assuming that the working current of LED is I (a), the current limiting resistor in series for each group is r = 3.9/i (Ohm). The power of resistor is p = 3.9 × I (watt)
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