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Random-phase optotriac driver

MOC3021 Internal Circuitry

Explore the internal circuitry and functional stages of MOC3021.

Package view

Inside MOC3021

Infrared emitter and light-triggered bilateral switch.

MOC3021 compact cutaway inputLED1and2,output4and6,pins3and5leftopen.
Functional organization, not a die photograph. Input and output have no conductive signal link.

Explore the circuit

Select a stage to see its role and connections

Optical input

The LED converts current into infrared light.

Insulating barrier

Only the optical signal crosses the package barrier.

Bilateral output

The bilateral output responds to the optical trigger and available circuit current.

Component view