I have a RL80-UR543 LED 8MM. How much voltage I need if I use a resistor of 100Ohm?
1 Answer
Forward Current (If) = 20 mA and
Forward Voltage (Vf) = 1.7V to 2.8V
is written on datasheet
- maximum voltage = 20mA*100ohm + 2.8V = 4.8V
-
\$\begingroup\$ I conntect it to a battery without any resistor and nothing happened. Bettery is 1.5v \$\endgroup\$– No NamerJan 8, 2019 at 20:31
-
\$\begingroup\$ I calculated theoretical maximum voltage according to your requirements. Using leds without current control not a good way. \$\endgroup\$– KorayJan 9, 2019 at 5:56