Tools & Accessories
LED Red
৳2
Standard 5 mm red LED with a forward voltage around 2.0V, so it needs about a 220Ω series resistor on a 5V rail.
Red is the lowest forward voltage of the common colours, which makes it the most forgiving on low supply voltages and the brightest for a given current.
What you can build
- Power and status indicators
- Error and warning lights
- Any first electronics lesson on current limiting
Not sure it will work? Test your circuit free in Tekko Sim — on your phone, in Bangla or English.
| Category | Tools & Accessories |
| Model no. | 5mm red |
| Availability | In stock |
| In stock | 25 pcs |
| Delivery | Cash on Delivery, nationwide Bangladesh |
| Colour | red |
| Size | 5 mm through-hole |
| Forward Voltage | roughly 1.8–2.2V |
| Forward Current | 20 mA typical |
| Suggested Resistor on 5V | 220Ω |
| Suggested Resistor on 3.3V | 100Ω |
| Polarity | long leg is the anode, positive |
Questions about the LED Red
Which resistor should I use with a red LED?
On a 5V supply, 220Ω gives roughly 14 mA, which is bright and safely within the LED's rating. 330Ω works too and is slightly dimmer. On 3.3V use 100Ω.
Can I connect the LED without a resistor?
No. An LED has almost no internal resistance, so without one it draws whatever the supply can deliver and burns out, often taking the microcontroller pin with it.
Which leg is positive?
The longer leg is the anode and goes to positive. There is also a flat notch on the rim of the case next to the cathode, which is the negative side.
More in Tools & Accessories
All tools & accessories →
