This Product Selection Guide contains information to help select products in the Transistor, Photovolatic Output Optoisolators category on DigiKey.com
Transistor or photovoltaic output optoisolators use light to transmit information across an electrical insulation barrier, usually for safety or functional reasons. They are distinguished from other optoisolator types by their use of a simple phototransistor or photovoltaic cell (solar cell) as an output device. The outputs of these devices do not require an external power source for operation and are analog in character, allowing their use for transmitting analog information between circuits which cannot be electrically connected.
SelectionCharacteristics
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.
Current Transfer Ratio (Min): Characterizes transfer function efficacy; the specified minimum ratio of output current to input current.
Current Transfer Ratio (Max): Characterizes transfer function efficacy; the specified maximum ratio of output current to input current.
Turn On / Turn Off Time (Typ): Characterizes the time delay between application or removal of an input signal and appearance of the result at a device’s output.
Rise / Fall Time (Typ): Characterizes the amount of time required for a device output to transition from low to high/high to low states, which are commonly defined as 10% and 90% of the supply voltage that powers the output being measured.
Input Type: Indicates which voltage type the device is designed to accept on its input side.
Output Type: Indicates which signal type the device outputs.
Voltage - Output (Max): Indicates the maximum output voltage that a device is capable of producing or accommodating, subject to specified limitations or constraints.
Current - Output / Channel: Typically this indicates the maximum current an output channel can provide.
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.
Vce Saturation (Max): Characterizes the maximum on-state voltage appearing across a device output for devices incorporating a bipolar-type transistor output.
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 mounted
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’s 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.
ProductExamples
| MFR PART # | LTV-817S-TA1 |
|---|---|
| DIGI-KEY PART # | 160-1893-2-ND - Tape & Reel (TR) |
| MANUFACTURER | Lite-On Inc. |
| DESCRIPTION | Optoisolator Transistor Output 5000Vrms 1 Channel 4-SMD |
| DATASHEET | Click Here |
| MFR PART # | APV2111VY |
|---|---|
| DIGI-KEY PART # | 255-3874-2-ND - Tape & Reel (TR) |
| MANUFACTURER | Panasonic Electric Works |
| DESCRIPTION | Optoisolator Photovoltaic Output 1500Vrms 1 Channel 4-SSOP |
| DATASHEET | Click Here |
| MFR PART # | 4N37M |
|---|---|
| DIGIKEY PART # | 4N37MFS-ND |
| MANUFACTURER | onsemi |
| DESCRIPTION | Optoisolator Transistor with Base Output 4170Vrms 1 Channel 6-DIP |
| DATASHEET | Click Here |
| MFR PART # | 8324610000 |
|---|---|
| DIGIKEY PART # | 281-3345-ND |
| MANUFACTURER | Weidmüller |
| DESCRIPTION | Optoisolator Transistor Output 1 Channel |
| DATASHEET | Click Here |
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MediaLinks
Articles
Galvanic Isolation for IoT Sensors
Linear Optical Isolation for Safe Sensor Operation
Product Training Modules
Introduction to Optoisolators - TT Electronics