The FT-M452 and FT-M453 devices each consist of an infrared emitting diode, optically coupled to a high speed photo detector transistor.
A separate connection for the photodiode bias and output-transistor collector increase the speed by several orders of magnitude over conventional phototransistor couplers by reducing the base-collector capacitance of the input transistor. The FT-M600, FT-M601 and FT-M611 are consists of an infrared emitting diode optically coupled to a high speed integrated photo detector logic gate with a strobable output. The devices are packaged in a 5-pin small outline package which conforms to the standard footprint.