This Product Selection Guide contains information to help select products in the Triac, SCR Output Optoisolators category on DigiKey.com
Triac and SCR output optoisolators allow bi-directional or unidirectional control of an AC (alternating current) source while providing isolation between the control and load circuits. An LED is optically coupled to a photodiode in a single device package. The photodiode controls the gate of the Triac or SCR and may include zero cross circuity. These optoisolators are selected by on-state current, forward voltage, turn on time, and mounting type.
SelectionCharacteristics
Output Type: Indicates which signal type the device outputs.
Zero Crossing Circuit: Indicates whether or not a device contains circuitry to inhibit triggering when the voltage present across the output terminals exceeds a manufacturer-defined threshold.
Number of Channels: The number of separate isolation channels available within the device.
Voltage - Isolation: The maximum voltage difference that can be observed across the device’s isolation barrier before breakdown occurs and isolation is lost.
Voltage - Off State: Indicates the maximum instantaneous voltage that may be repetitively/continuously applied to a device in a non-conducting state without causing damage.
Static dV/dt (Min): Characterizes resistance to false triggering; the minimum time rate of voltage change across the device output that a fully-commutated device must withstand under manufacturer-defined test conditions.
Current - LED Trigger (Ift) (Max): Input current required to trigger output into a latched conducting state, actual values vary with temperature.
Current - On State (It (RMS)) (Max): The rated maximum RMS (root mean square) current carrying capacity of a device, typically specified for sinusoidal current waveforms at 50/60 Hz.
Current - Hold (Ih): Characterizes the minimum current flow through a device’s output that will maintain the output in a conducting state.
Turn On Time: Characterizes the time delay between application of a control input and the device output achieving an ‘On’ state.
Voltage - Forward (Vf) (Typ): Characterizes the device’s forward voltage drop across its internal diodes while in an ‘Off’ state.
Current - DC Forward (If) (Max): Characterizes the device’s forward current through its internal diodes while in an ‘On’ state.
Operating Temperature: Recommended operating temperature, typically given in a range or as a maximum. Exceeding these temperatures may affect performance or damage the device and other system components.
Mounting Type: Indicates how the device is attached.
Package / Case: Indicates the type of protective case used on an electronic component to allow easy handling, installation, and protection. This selection was determined to be the closest industry standard applicable to the supplier device packaging. Typically it is best to check the actual dimensions from the datasheet rather than depend on this terminology when designing your circuit.
Supplier Device Package: This is what the manufacturer calls the package of this device. They are manufacturer specific. It is typically best to use the actual dimensions from the datasheets rather than to go by this terminology when designing your circuit.
Approval Agency: An indication that the product meets the minimum safety standards of an approving agency. These agencies are either government entities or private third-party labs that protect consumer safety.
ProductExamples
| MFR PART # | TLP266J(T7-TPL,E |
|---|---|
| DIGIKEY PART # | TLP266J(T7-TPLETR-ND - Tape & Reel (TR) |
| MANUFACTURER | Toshiba Semiconductor and Storage |
| DESCRIPTION | Optoisolator Triac Output 3750Vrms 1 Channel 6-SOP |
| DATASHEET | Click Here |
| MFR PART # | VO2223A |
|---|---|
| DIGIKEY PART # | 751-1490-5-ND |
| MANUFACTURER | Vishay Semiconductor Opto Division |
| DESCRIPTION | Optoisolator Triac, Power Output 5300Vrms 1 Channel 8-DIP |
| DATASHEET | Click Here |
| MFR PART # | MOC3023SR2M |
|---|---|
| DIGIKEY PART # | MOC3023SR2MTR-ND - Tape & Reel (TR) |
| MANUFACTURER | onsemi |
| DESCRIPTION | Optoisolator Triac Output 4170Vrms 1 Channel 6-SMD |
| DATASHEET | Click Here |
| MFR PART # | MOC3043M |
|---|---|
| DIGIKEY PART # | MOC3043M-ND |
| MANUFACTURER | onsemi |
| DESCRIPTION | Optoisolator Triac Output 4170Vrms 1 Channel 6-DIP |
| DATASHEET | Click Here |
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MediaLinks
Videos
Articles
Galvanic Isolation for IoT Sensors
Linear Optical Isolation for Safe Sensor Operation
Product Training Modules
Introduction to Optoisolators - TT Electronics