Velleman К8088 Manuel d'utilisateur télécharger pdf (Page 10)

LED:

 LEDs require a series resistor (R4, R5 or R6)

Determine led voltage drop (Check manufacturer datasheet).

Rule of thumb: red: 1.7V, green: 2V, blue: 3..4V).

Next, check required LED current.

Example:

Red LED, 1.7V drop, required current: 20mA

Resistor calculation: (12V-1.7V) / 0.020 = 515 ohm (choose nearest value,

e.g. 560 ohm)

Resistor power rating calculation: (12V-1.7V) x (12V-1.7V) / 560 = 0.19W

(choose a 0.25W resistor)

Connection

12VDC

C (-)

A (+)

1 2 ... 5 6 7 8 9 10 11 12 13 14 15 16

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Velleman К8088 Manuel d'utilisateur Page 10