MOC3021 Triac drive Optoisolator pinout Details:
The MOC3021 comes in an internal light-emitting diode and a TRIAC based light activating based transistor. This optocoupler provides protection from HIGH resistive and inductive loads. It has the ability to flow the current up to 1A. In HIGH load the operating temperature always affects the circuit performance, but MOC3021 has the ability to operate in HIGH temperature and it also increases the optocoupler life.
How and Where to use MOC3021 Phototransistor Optocoupler
The IC could work with any TTL device or any microcontroller but to operate it properly with high load external TRIAC is suggested due to some safety measurements and due to different magnitudes of the IC. The output will be flow only when the input is HIGH. First, take a look at the given circuit.

MOC3021 Testing Circuit:
In this example, we are going to use the MOC3021 in testing method. We are going to use a TRIAC, lamp, 220 AC, resistors and an diode. In this circuit, switch will be used to act as on or off moc3021 will be used to turn on and off the lamp through the TRIAC. We can use switch directly with the MOC3021 with the help of resistors but here we are going to use a variable resistor. The variable resistor will be able to adjust the Triac intensity.
Optocoupler Features:
1. High isolation voltages, which is not for AC current. This ability only exists a TRIAC based optocoupler.
2. stability of the device is much reliable for any high load.
3. Soldering temperature for optocoupler is much high.
4. The output pins have the ability to hold the high load at off state which makes it reliable for any switching device at a normal level.
5. Due to the internal IR transmitting function, the input device remains securely used with the IC to control it.
6. Due to non-zero ability, the IC can give the output of different magnitudes. It makes the IC control the load at different from the use of external TRIACS.
7. The temperature is the important factor when we need to control the high load and IC can operate within the high temperature and it can also store the temperature.
8. The IC comes only in one 6 pin package which is PDIP but it is usable with any circuit.

1. The IC has minimum input forward voltage is 1.3V
2. To the trigger the LED forward current should be 15mA minimum otherwise led may not operate.
3. The TRIAC within the IC has a high output voltage range which is 400V maximum. More than 400 will first heat up the IC then it will burn.
4. TRIAC has peak output current range of 1.2A.
5. The Power dissipation for IC at 25 degrees is 300mW.
6. The operating temperature range for IC is -40 to 100 degree and it has the ability to store the temperature up to -55 to 150 degree.
7. The Soldering temperature range for IC is 260-degree maximum then IC will burn during soldering.

MOC3021 Optocoupler APPLICATIONS
1. The IC can operate with all European applications up to 240V of AC.
2. MOC3021 is used to operate high load TRIAC.
3. In industrial applications, the IC has vast usage.
4. IC also used as switching in Traffic Lights.
5. Motor control and Fan speed control also uses MOC3021 with the microcontroller.
6. Vending Machines and SSR (Solid State Relays) also use IC to operate

About the Author


Hello! My Dear Friends. I am Subramanian. I am writing posts on androiderode about Electronics testing and equipments.

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