RGB LED

The RGB LED part models a common-cathode package with three separate Shockley diode channels. Red, green, and blue each draw their own nonlinear current. The rendered colour is a teaching visualisation of those channel currents, not a calibrated optical-spectrum, efficacy, or colour-mixing model.

Pinout

PinLabelDescription
r_aR+Red anode
g_aG+Green anode
b_aB+Blue anode
com_kKCommon cathode (shared GND)

Default forward voltages

ChannelVf
Red1.8 V
Green2.0 V
Blue3.0 V

These can be overridden via the Inspector properties panel.

Current limiting

The LED has no internal series resistance. You must connect a resistor on each anode pin to prevent overcurrent. A 220 Ω resistor with a 5 V supply gives approximately 14 mA per channel.

The engine accumulates an I²-shaped overcurrent stress from the highest channel current. Enough sustained stress above the default 20 mA rating latches the whole RGB package open for the rest of the failure session; it does not fail individual colour dice independently. Use Clear failures or start a fresh session to reset this simulated damage state. The threshold is a deterministic teaching rule, not a real LED lifetime or pulse-rating curve.

Common-cathode only

de:volt models only common-cathode polarity. Connect com_k to GND.

Example circuit

Arduino D3 ─── 220 Ω ─── R+
Arduino D5 ─── 220 Ω ─── G+  ──  [RGB LED] ── K ─── GND
Arduino D6 ─── 220 Ω ─── B+

Load the built-in RGB Colour Cycle example from the Sketch panel to see PWM-driven channel-current visualisation.

Model limits

Included: one nonlinear junction, solved forward current, and current-based brightness input for each colour, plus package-level accumulated overcurrent failure.

Not included: optical spectrum, calibrated luminous intensity or gamma, package optics, channel thermal coupling, junction self-heating, reverse-breakdown damage, pulse SOA, wavelength drift, and time-to-failure prediction. Select the LED to see the same Included / Not included disclosure in the Inspector.