The KP40101B is an Optocouplers DIP-4 RoHS manufactured by Cosmo. It is a 4-pin dip package that isolates input and output signals, preventing high voltage from affecting the input side. It has a 6 to 9 kV peak isolation voltage between insulation test voltage pins, and the coupling current transfer ratio is 10% over a defined temperature range. It features high common-mode rejection ratio, low forward voltage input, wide operating temperature range, and a wide range of CTR parameters. It is RoHS compliant and suitable for a variety of applications such as telecommunication and measurement systems, medical systems, and security systems.