4N25 OPTOCOUPLER Phototransistor

The 4N25 OPTOCOUPLER Phototransistor combines an infrared LED and a phototransistor in a compact single-package device to deliver reliable electrical isolation and optical signal transfer between circuits. Engineered for robust noise immunity and consistent coupling efficiency, the 4N25 supports precise signal transmission in demanding electronic systems. Collector-Emitter Voltage: 30V, supporting a range of circuit configurations. Current Transfer Ratio (CTR): 50% to 600%, providing efficient conversion from input LED current to output transistor current. Isolation Voltage: 5000 VRMS, offering substantial electrical separation for safety and interference reduction. Response Time: 3 µs, suitable for fast switching and time-sensitive applications. Operating Temperature Range: -55°C to 100°C, enabling reliable operation across harsh temperature conditions. Compared with standard optocouplers, the 4N25 delivers an elevated isolation voltage and a broadly specified current transfer ratio, making it particularly well suited where secure galvanic separation and adaptable signal gain are required. The phototransistor output is precisely aligned with the internal LED to maximize optical coupling and minimize noise and distortion. This yields consistent performance across a wide range of operating conditions and helps maintain signal integrity in communication interfaces, microprocessor input isolation, and industrial control systems. Its combination of high isolation rating, wide CTR range, and fast response time makes the 4N25 OPTOCOUPLER Phototransistor a practical choice for applications that demand both safety and rapid signal switching.