Single led - Leds in series - Leds in parallel

Voltage drop is typically 1.9 - 2.1V for Red, Yellow & Orange, 3.0 - 3.3V for White, Blue, Green & UV and 1.2V for Infrared LEDs. Current is usually between 10 - 20mA. Supply Voltage - depends what you have at your disposal, typically 3V, 6V or 12V source.

Single led:
Single led with single resistor
Supply Voltage
VOLTS
Voltage Drop Across LED
VOLTS
Desired LED Current
MILLIAMPS



Calculated Limiting Resistor
OHMS
Nearest higher rated 10% resistor

Calculated Resistor Wattage
WATTS
Safe pick is a resistor with
power rating of
WATTS

Leds in series:
Several leds in series with one resistor
Supply Voltage
VOLTS
Voltage Drop Across LED
VOLTS
Desired LED Current
MILLIAMPS
How many leds connected




Calculated Limiting Resistor
OHMS
Nearest higher rated 10% resistor

Calculated Resistor Wattage
WATTS
Safe pick is a resistor with
power rating of
WATTS

Leds in parallel:
Several leds connected parallel with one resistor
Supply Voltage
VOLTS
Voltage Drop Across LED
VOLTS
Desired LED Current
MILLIAMPS
How many leds connected




Calculated Limiting Resistor
OHMS
Nearest higher rated 10% resistor

Calculated Resistor Wattage
WATTS
Safe pick is a resistor with
power rating of
WATTS