The package form of photoelectric coupler can be divided into coaxial type, double row direct inserting type, To package type, flat package type, SMD package type, optical fiber transmission type, etc. But in the production or maintenance of electronic enthusiasts are often used in the form of packaging almost all of the plastic-DIP, flat packaging and SMD package these 3 categories, and its pins are divided into 4, 6, 8, 12, 16, 24 feet.
The types of optocoupler are various, if divided according to the output form, mainly have photosensitive diode-type, general-purpose (that is, photosensitive transistor type, and there are divided into lead-free and base-pole leads), Darlington (composite transistor) type, two-way symmetry, high-speed, photosensitive resistor type, photovoltaic cell type, photosensitive field effect tube type, photosensitive thyristor type (also divided into unidirectional thyristor and two-way thyristor), optical integrated circuit type.
Depending on the transmission signal, the optical coupler
can be divided into two categories: non-linear (digital) optocoupler and inear (analog) optocoupler. Because the speed of transmission signal is different, it can be divided into low-speed photoelectric coupler (photosensitive transistor, optical cell output type) and high-speed photoelectric coupler (photosensitive diode band signal processing circuit or photosensitive integrated circuit output type). According to the isolation characteristics, it also can be divided into ordinary isolation photoelectric coupler (general optical insulating plastic potting less than 5kV, air seals below 2kV) and high-voltage isolation optocoupler (which can be divided into 10kV, 20kV, 30kV, etc.). According to the number of transmission signal channels, it can be divided into a single channel, dual channel and multi-channel photoelectric coupler.