This part is a kind of semiconductor called 4N38.

Function of this product has HIGH VOLTAGE PHOTOTRANSISTOR OPTOCOUPLERS.

Manufacturers : Fairchild Semiconductor

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HIGH VOLTAGE PHOTOTRANSISTOR OPTOCOUPLERS DESCRIPTION The H11DX and 4N38 are phototransistor-type optically coupled optoisolators. An infrared emitting diode manufactured from specially grown gallium arsenide is selectively coupled with a high voltage NPN silicon phototransistor. The device is supplied in a standard plastic six-pin dual-in-line package. H11D1 H11D2 H11D3 H11D4 4N38 FEATURES • High Voltage - H11D1, H11D2, BVCER = 300 V - H11D3, H11D4, BVCER = 200 V • High isolation voltage - 5300 VAC RMS - 1 minute - 7500 VAC PEAK - 1 minute • Underwriters Laboratory (UL) recognized File# E90700 ANODE 1 6 BASE APPLICATIONS • • • • • Power supply regulators Digital logic inputs Microprocessor inputs Appliance sensor systems Industrial controls CATHODE 2 5 COLLECTOR N/ [ ... ]

4N38 PDF Datasheet Download